Bone loss due to osteoclastic activity.
A specialized CONNECTIVE TISSUE that is the main constituent of the SKELETON. The principle cellular component of bone is comprised of OSTEOBLASTS; OSTEOCYTES; and OSTEOCLASTS, while FIBRILLAR COLLAGENS and hydroxyapatite crystals form the BONE MATRIX.
A large multinuclear cell associated with the BONE RESORPTION. An odontoclast, also called cementoclast, is cytomorphologically the same as an osteoclast and is involved in CEMENTUM resorption.
The continuous turnover of BONE MATRIX and mineral that involves first an increase in BONE RESORPTION (osteoclastic activity) and later, reactive BONE FORMATION (osteoblastic activity). The process of bone remodeling takes place in the adult skeleton at discrete foci. The process ensures the mechanical integrity of the skeleton throughout life and plays an important role in calcium HOMEOSTASIS. An imbalance in the regulation of bone remodeling's two contrasting events, bone resorption and bone formation, results in many of the metabolic bone diseases, such as OSTEOPOROSIS.
Resorption in which cementum or dentin is lost from the root of a tooth owing to cementoclastic or osteoclastic activity in conditions such as trauma of occlusion or neoplasms. (Dorland, 27th ed)
The amount of mineral per square centimeter of BONE. This is the definition used in clinical practice. Actual bone density would be expressed in grams per milliliter. It is most frequently measured by X-RAY ABSORPTIOMETRY or TOMOGRAPHY, X RAY COMPUTED. Bone density is an important predictor for OSTEOPOROSIS.
A transmembrane protein belonging to the tumor necrosis factor superfamily that specifically binds RECEPTOR ACTIVATOR OF NUCLEAR FACTOR-KAPPA B and OSTEOPROTEGERIN. It plays an important role in regulating OSTEOCLAST differentiation and activation.
The growth and development of bones from fetus to adult. It includes two principal mechanisms of bone growth: growth in length of long bones at the epiphyseal cartilages and growth in thickness by depositing new bone (OSTEOGENESIS) with the actions of OSTEOBLASTS and OSTEOCLASTS.
A secreted member of the TNF receptor superfamily that negatively regulates osteoclastogenesis. It is a soluble decoy receptor of RANK LIGAND that inhibits both CELL DIFFERENTIATION and function of OSTEOCLASTS by inhibiting the interaction between RANK LIGAND and RECEPTOR ACTIVATOR OF NUCLEAR FACTOR-KAPPA B.
Tumors or cancer located in bone tissue or specific BONES.
Bone-forming cells which secrete an EXTRACELLULAR MATRIX. HYDROXYAPATITE crystals are then deposited into the matrix to form bone.
Organic compounds which contain P-C-P bonds, where P stands for phosphonates or phosphonic acids. These compounds affect calcium metabolism. They inhibit ectopic calcification and slow down bone resorption and bone turnover. Technetium complexes of diphosphonates have been used successfully as bone scanning agents.
The process of bone formation. Histogenesis of bone including ossification.
Resorption or wasting of the tooth-supporting bone (ALVEOLAR PROCESS) in the MAXILLA or MANDIBLE.
Diseases of BONES.
A tumor necrosis factor receptor family member that is specific for RANK LIGAND and plays a role in bone homeostasis by regulating osteoclastogenesis. It is also expressed on DENDRITIC CELLS where it plays a role in regulating dendritic cell survival. Signaling by the activated receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.
Extracellular substance of bone tissue consisting of COLLAGEN fibers, ground substance, and inorganic crystalline minerals and salts.
Cells contained in the bone marrow including fat cells (see ADIPOCYTES); STROMAL CELLS; MEGAKARYOCYTES; and the immediate precursors of most blood cells.
An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC
The soft tissue filling the cavities of bones. Bone marrow exists in two types, yellow and red. Yellow marrow is found in the large cavities of large bones and consists mostly of fat cells and a few primitive blood cells. Red marrow is a hematopoietic tissue and is the site of production of erythrocytes and granular leukocytes. Bone marrow is made up of a framework of connective tissue containing branching fibers with the frame being filled with marrow cells.
The disintegration and assimilation of the dead FETUS in the UTERUS at any stage after the completion of organogenesis which, in humans, is after the 9th week of GESTATION. It does not include embryo resorption (see EMBRYO LOSS).
Reduction of bone mass without alteration in the composition of bone, leading to fractures. Primary osteoporosis can be of two major types: postmenopausal osteoporosis (OSTEOPOROSIS, POSTMENOPAUSAL) and age-related or senile osteoporosis.
Dissolution of bone that particularly involves the removal or loss of calcium.
The SKELETON of the HEAD including the FACIAL BONES and the bones enclosing the BRAIN.
A cysteine protease that is highly expressed in OSTEOCLASTS and plays an essential role in BONE RESORPTION as a potent EXTRACELLULAR MATRIX-degrading enzyme.
Excessive formation of dense trabecular bone leading to pathological fractures; OSTEITIS; SPLENOMEGALY with infarct; ANEMIA; and extramedullary hemopoiesis (HEMATOPOIESIS, EXTRAMEDULLARY).
A polypeptide hormone (84 amino acid residues) secreted by the PARATHYROID GLANDS which performs the essential role of maintaining intracellular CALCIUM levels in the body. Parathyroid hormone increases intracellular calcium by promoting the release of CALCIUM from BONE, increases the intestinal absorption of calcium, increases the renal tubular reabsorption of calcium, and increases the renal excretion of phosphates.
A nonhormonal medication for the treatment of postmenopausal osteoporosis in women. This drug builds healthy bone, restoring some of the bone loss as a result of osteoporosis.
Resorption of calcified dental tissue, involving demineralization due to reversal of the cation exchange and lacunar resorption by osteoclasts. There are two types: external (as a result of tooth pathology) and internal (apparently initiated by a peculiar inflammatory hyperplasia of the pulp). (From Jablonski, Dictionary of Dentistry, 1992, p676)
Metabolic bone diseases are a group of disorders that affect the bones' structure and strength, caused by disturbances in the normal metabolic processes involved in bone formation, resorption, or mineralization, including conditions like osteoporosis, osteomalacia, Paget's disease, and renal osteodystrophy.
The longest and largest bone of the skeleton, it is situated between the hip and the knee.
Vitamin K-dependent calcium-binding protein synthesized by OSTEOBLASTS and found primarily in BONES. Serum osteocalcin measurements provide a noninvasive specific marker of bone metabolism. The protein contains three residues of the amino acid gamma-carboxyglutamic acid (Gla), which, in the presence of CALCIUM, promotes binding to HYDROXYAPATITE and subsequent accumulation in BONE MATRIX.
Renewal or repair of lost bone tissue. It excludes BONY CALLUS formed after BONE FRACTURES but not yet replaced by hard bone.
A diphosphonate which affects calcium metabolism. It inhibits ectopic calcification and slows down bone resorption and bone turnover.
The most common form of fibrillar collagen. It is a major constituent of bone (BONE AND BONES) and SKIN and consists of a heterotrimer of two alpha1(I) and one alpha2(I) chains.
A peptide hormone that lowers calcium concentration in the blood. In humans, it is released by thyroid cells and acts to decrease the formation and absorptive activity of osteoclasts. Its role in regulating plasma calcium is much greater in children and in certain diseases than in normal adults.
The second longest bone of the skeleton. It is located on the medial side of the lower leg, articulating with the FIBULA laterally, the TALUS distally, and the FEMUR proximally.
Metabolic disorder associated with fractures of the femoral neck, vertebrae, and distal forearm. It occurs commonly in women within 15-20 years after menopause, and is caused by factors associated with menopause including estrogen deficiency.
The grafting of bone from a donor site to a recipient site.
An enzyme that catalyzes the conversion of an orthophosphoric monoester and water to an alcohol and orthophosphate. EC
X-RAY COMPUTERIZED TOMOGRAPHY with resolution in the micrometer range.
Mature osteoblasts that have become embedded in the BONE MATRIX. They occupy a small cavity, called lacuna, in the matrix and are connected to adjacent osteocytes via protoplasmic projections called canaliculi.
Abnormally high level of calcium in the blood.
Orthodontic techniques used to correct the malposition of a single tooth.
A disease marked by repeated episodes of increased bone resorption followed by excessive attempts at repair, resulting in weakened, deformed bones of increased mass. The resultant architecture of the bone assumes a mosaic pattern in which the fibers take on a haphazard pattern instead of the normal parallel symmetry.
Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.
Breaks in bones.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
Process by which organic tissue becomes hardened by the physiologic deposit of calcium salts.
One of a pair of irregularly shaped quadrilateral bones situated between the FRONTAL BONE and OCCIPITAL BONE, which together form the sides of the CRANIUM.
The surgical removal of one or both ovaries.
The thickest and spongiest part of the maxilla and mandible hollowed out into deep cavities for the teeth.
A hydroxylated form of the imino acid proline. A deficiency in ASCORBIC ACID can result in impaired hydroxyproline formation.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.
The transference of BONE MARROW from one human or animal to another for a variety of purposes including HEMATOPOIETIC STEM CELL TRANSPLANTATION or MESENCHYMAL STEM CELL TRANSPLANTATION.
Synthetic or natural materials for the replacement of bones or bone tissue. They include hard tissue replacement polymers, natural coral, hydroxyapatite, beta-tricalcium phosphate, and various other biomaterials. The bone substitutes as inert materials can be incorporated into surrounding tissue or gradually replaced by original tissue.
A mononuclear phagocyte colony-stimulating factor (M-CSF) synthesized by mesenchymal cells. The compound stimulates the survival, proliferation, and differentiation of hematopoietic cells of the monocyte-macrophage series. M-CSF is a disulfide-bonded glycoprotein dimer with a MW of 70 kDa. It binds to a specific high affinity receptor (RECEPTOR, MACROPHAGE COLONY-STIMULATING FACTOR).
The largest of three bones that make up each half of the pelvic girdle.
Bone-growth regulatory factors that are members of the transforming growth factor-beta superfamily of proteins. They are synthesized as large precursor molecules which are cleaved by proteolytic enzymes. The active form can consist of a dimer of two identical proteins or a heterodimer of two related bone morphogenetic proteins.
The physiologically active form of vitamin D. It is formed primarily in the kidney by enzymatic hydroxylation of 25-hydroxycholecalciferol (CALCIFEDIOL). Its production is stimulated by low blood calcium levels and parathyroid hormone. Calcitriol increases intestinal absorption of calcium and phosphorus, and in concert with parathyroid hormone increases bone resorption.
A noninvasive method for assessing BODY COMPOSITION. It is based on the differential absorption of X-RAYS (or GAMMA RAYS) by different tissues such as bone, fat and other soft tissues. The source of (X-ray or gamma-ray) photon beam is generated either from radioisotopes such as GADOLINIUM 153, IODINE 125, or Americanium 241 which emit GAMMA RAYS in the appropriate range; or from an X-ray tube which produces X-RAYS in the desired range. It is primarily used for quantitating BONE MINERAL CONTENT, especially for the diagnosis of OSTEOPOROSIS, and also in measuring BONE MINERALIZATION.
A diphosphonate which affects calcium metabolism. It inhibits bone resorption and soft tissue calcification.
Adhesives used to fix prosthetic devices to bones and to cement bone to bone in difficult fractures. Synthetic resins are commonly used as cements. A mixture of monocalcium phosphate, monohydrate, alpha-tricalcium phosphate, and calcium carbonate with a sodium phosphate solution is also a useful bone paste.
A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of SKIN; CONNECTIVE TISSUE; and the organic substance of bones (BONE AND BONES) and teeth (TOOTH).
Thin outer membrane that surrounds a bone. It contains CONNECTIVE TISSUE, CAPILLARIES, nerves, and a number of cell types.
A ubiquitously expressed, secreted protein with bone resorption and renal calcium reabsorption activities that are similar to PARATHYROID HORMONE. It does not circulate in appreciable amounts in normal subjects, but rather exerts its biological actions locally. Overexpression of parathyroid hormone-related protein by tumor cells results in humoral calcemia of malignancy.
A non-metal element that has the atomic symbol P, atomic number 15, and atomic weight 31. It is an essential element that takes part in a broad variety of biochemical reactions.
A potent osteoinductive protein that plays a critical role in the differentiation of osteoprogenitor cells into OSTEOBLASTS.
Inflammation and loss of connective tissues supporting or surrounding the teeth. This may involve any part of the PERIODONTIUM. Periodontitis is currently classified by disease progression (CHRONIC PERIODONTITIS; AGGRESSIVE PERIODONTITIS) instead of age of onset. (From 1999 International Workshop for a Classification of Periodontal Diseases and Conditions, American Academy of Periodontology)
Inbred C57BL mice are a strain of laboratory mice that have been produced by many generations of brother-sister matings, resulting in a high degree of genetic uniformity and homozygosity, making them widely used for biomedical research, including studies on genetics, immunology, cancer, and neuroscience.
The emergence of a tooth from within its follicle in the ALVEOLAR PROCESS of the MAXILLA or MANDIBLE into the ORAL CAVITY. (Boucher's Clinical Dental Terminology, 4th ed)
Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
Tartrates are salts or esters of tartaric acid, primarily used in pharmaceutical industry as buffering agents, and in medical laboratories for the precipitation of proteins.
The largest and strongest bone of the FACE constituting the lower jaw. It supports the lower teeth.
One of a pair of irregularly shaped bones that form the upper jaw. A maxillary bone provides tooth sockets for the superior teeth, forms part of the ORBIT, and contains the MAXILLARY SINUS.
Cell surface receptors that bind TUMOR NECROSIS FACTORS and trigger changes which influence the behavior of cells.
A group of lysosomal proteinases or endopeptidases found in aqueous extracts of a variety of animal tissues. They function optimally within an acidic pH range. The cathepsins occur as a variety of enzyme subtypes including SERINE PROTEASES; ASPARTIC PROTEINASES; and CYSTEINE PROTEASES.
Proton-translocating ATPases that are involved in acidification of a variety of intracellular compartments.
Chronic nonsuppurative inflammation of periapical tissue resulting from irritation following pulp disease or endodontic treatment.
Maxillary diseases refer to various medical conditions primarily affecting the maxilla (upper jaw) bone, including inflammatory processes, tumors, cysts, or traumatic injuries, which may cause symptoms such as pain, swelling, or functional impairment.
Native, inorganic or fossilized organic substances having a definite chemical composition and formed by inorganic reactions. They may occur as individual crystals or may be disseminated in some other mineral or rock. (Grant & Hackh's Chemical Dictionary, 5th ed; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Elements of limited time intervals, contributing to particular results or situations.
Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.
The part of a tooth from the neck to the apex, embedded in the alveolar process and covered with cementum. A root may be single or divided into several branches, usually identified by their relative position, e.g., lingual root or buccal root. Single-rooted teeth include mandibular first and second premolars and the maxillary second premolar teeth. The maxillary first premolar has two roots in most cases. Maxillary molars have three roots. (Jablonski, Dictionary of Dentistry, 1992, p690)
A biosynthetic precursor of collagen containing additional amino acid sequences at the amino-terminal and carboxyl-terminal ends of the polypeptide chains.
An abnormal hardening or increased density of bone tissue.
Glycoproteins which contain sialic acid as one of their carbohydrates. They are often found on or in the cell or tissue membranes and participate in a variety of biological activities.
The tip or terminal end of the root of a tooth. (Jablonski, Dictionary of Dentistry, 1992, p62)
The most posterior teeth on either side of the jaw, totaling eight in the deciduous dentition (2 on each side, upper and lower), and usually 12 in the permanent dentition (three on each side, upper and lower). They are grinding teeth, having large crowns and broad chewing surfaces. (Jablonski, Dictionary of Dentistry, 1992, p821)
Calcium compounds used as food supplements or in food to supply the body with calcium. Dietary calcium is needed during growth for bone development and for maintenance of skeletal integrity later in life to prevent osteoporosis.
The relationship between the dose of an administered drug and the response of the organism to the drug.
Any of the eight frontal teeth (four maxillary and four mandibular) having a sharp incisal edge for cutting food and a single root, which occurs in man both as a deciduous and a permanent tooth. (Jablonski, Dictionary of Dentistry, 1992, p820)
A species of gram-negative, anaerobic, rod-shaped bacteria originally classified within the BACTEROIDES genus. This bacterium produces a cell-bound, oxygen-sensitive collagenase and is isolated from the human mouth.
The fibrous CONNECTIVE TISSUE surrounding the TOOTH ROOT, separating it from and attaching it to the alveolar bone (ALVEOLAR PROCESS).
A family of transcription factors characterized by the presence of highly conserved calcineurin- and DNA-binding domains. NFAT proteins are activated in the CYTOPLASM by the calcium-dependent phosphatase CALCINEURIN. They transduce calcium signals to the nucleus where they can interact with TRANSCRIPTION FACTOR AP-1 or NF-KAPPA B and initiate GENETIC TRANSCRIPTION of GENES involved in CELL DIFFERENTIATION and development. NFAT proteins stimulate T-CELL activation through the induction of IMMEDIATE-EARLY GENES such as INTERLEUKIN-2.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
Unstable isotopes of calcium that decay or disintegrate emitting radiation. Ca atoms with atomic weights 39, 41, 45, 47, 49, and 50 are radioactive calcium isotopes.
Either of a pair of compound bones forming the lateral (left and right) surfaces and base of the skull which contains the organs of hearing. It is a large bone formed by the fusion of parts: the squamous (the flattened anterior-superior part), the tympanic (the curved anterior-inferior part), the mastoid (the irregular posterior portion), and the petrous (the part at the base of the skull).
Cell surface proteins that bind calcitonin and trigger intracellular changes which influence the behavior of cells. Calcitonin receptors outside the nervous system mediate the role of calcitonin in calcium homeostasis. The role of calcitonin receptors in the brain is not well understood.
A negatively-charged extracellular matrix protein that plays a role in the regulation of BONE metabolism and a variety of other biological functions. Cell signaling by osteopontin may occur through a cell adhesion sequence that recognizes INTEGRIN ALPHA-V BETA-3.
A hollow part of the alveolar process of the MAXILLA or MANDIBLE where each tooth fits and is attached via the periodontal ligament.
VERTEBRAE in the region of the lower BACK below the THORACIC VERTEBRAE and above the SACRAL VERTEBRAE.
The bonelike rigid connective tissue covering the root of a tooth from the cementoenamel junction to the apex and lining the apex of the root canal, also assisting in tooth support by serving as attachment structures for the periodontal ligament. (Jablonski, Dictionary of Dentistry, 1992)
The spinal or vertebral column.
The outer shorter of the two bones of the FOREARM, lying parallel to the ULNA and partially revolving around it.
Physiologic loss of the primary dentition. (Zwemer, Boucher's Clinical Dental Terminology, 4th ed)
A technique for maintenance or growth of animal organs in vitro. It refers to three-dimensional cultures of undisaggregated tissue retaining some or all of the histological features of the tissue in vivo. (Freshney, Culture of Animal Cells, 3d ed, p1)
Production of a radiographic image of a small or very thin object on fine-grained photographic film under conditions which permit subsequent microscopic examination or enlargement of the radiograph at linear magnifications of up to several hundred and with a resolution approaching the resolving power of the photographic emulsion (about 1000 lines per millimeter).
A polypeptide that consists of the 1-34 amino-acid fragment of human PARATHYROID HORMONE, the biologically active N-terminal region. The acetate form is given by intravenous infusion in the differential diagnosis of HYPOPARATHYROIDISM and PSEUDOHYPOPARATHYROIDISM. (Reynolds JEF(Ed): Martindale: The Extra Pharmacopoeia (electronic version). Micromedex, Inc, Englewood, CO, 1995)
Infections with bacteria of the family BACTEROIDACEAE.
A soluble factor produced by MONOCYTES; MACROPHAGES, and other cells which activates T-lymphocytes and potentiates their response to mitogens or antigens. Interleukin-1 is a general term refers to either of the two distinct proteins, INTERLEUKIN-1ALPHA and INTERLEUKIN-1BETA. The biological effects of IL-1 include the ability to replace macrophage requirements for T-cell activation.
'Mandibular diseases' refer to various medical conditions that primarily affect the structure, function, or health of the mandible (lower jawbone), including but not limited to infections, tumors, developmental disorders, and degenerative diseases.
Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
A technique of culturing mixed cell types in vitro to allow their synergistic or antagonistic interactions, such as on CELL DIFFERENTIATION or APOPTOSIS. Coculture can be of different types of cells, tissues, or organs from normal or disease states.
A malignancy of mature PLASMA CELLS engaging in monoclonal immunoglobulin production. It is characterized by hyperglobulinemia, excess Bence-Jones proteins (free monoclonal IMMUNOGLOBULIN LIGHT CHAINS) in the urine, skeletal destruction, bone pain, and fractures. Other features include ANEMIA; HYPERCALCEMIA; and RENAL INSUFFICIENCY.
A highly glycosylated and sulfated phosphoprotein that is found almost exclusively in mineralized connective tissues. It is an extracellular matrix protein that binds to hydroxyapatite through polyglutamic acid sequences and mediates cell attachment through an RGD sequence.
The hard portion of the tooth surrounding the pulp, covered by enamel on the crown and cementum on the root, which is harder and denser than bone but softer than enamel, and is thus readily abraded when left unprotected. (From Jablonski, Dictionary of Dentistry, 1992)
Transport proteins that carry specific substances in the blood or across cell membranes.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
The structures surrounding and supporting the tooth. Periodontium includes the gum (GINGIVA), the alveolar bone (ALVEOLAR PROCESS), the DENTAL CEMENTUM, and the PERIODONTAL LIGAMENT.
Intracellular receptors that can be found in the cytoplasm or in the nucleus. They bind to extracellular signaling molecules that migrate through or are transported across the CELL MEMBRANE. Many members of this class of receptors occur in the cytoplasm and are transported to the CELL NUCLEUS upon ligand-binding where they signal via DNA-binding and transcription regulation. Also included in this category are receptors found on INTRACELLULAR MEMBRANES that act via mechanisms similar to CELL SURFACE RECEPTORS.
The inner and longer bone of the FOREARM.
The TARSAL BONES; METATARSAL BONES; and PHALANGES OF TOES. The tarsal bones consists of seven bones: CALCANEUS; TALUS; cuboid; navicular; internal; middle; and external cuneiform bones. The five metatarsal bones are numbered one through five, running medial to lateral. There are 14 phalanges in each foot, the great toe has two while the other toes have three each.
Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.
Glycoproteins found on the membrane or surface of cells.
Hydroxy analogs of vitamin D 3; (CHOLECALCIFEROL); including CALCIFEDIOL; CALCITRIOL; and 24,25-DIHYDROXYVITAMIN D 3.
Polymerized methyl methacrylate monomers which are used as sheets, moulding, extrusion powders, surface coating resins, emulsion polymers, fibers, inks, and films (From International Labor Organization, 1983). This material is also used in tooth implants, bone cements, and hard corneal contact lenses.
One of the eight permanent teeth, two on either side in each jaw, between the canines (CUSPID) and the molars (MOLAR), serving for grinding and crushing food. The upper have two cusps (bicuspid) but the lower have one to three. (Jablonski, Dictionary of Dentistry, 1992, p822)
Bone in humans and primates extending from the SHOULDER JOINT to the ELBOW JOINT.
The constricted portion of the thigh bone between the femur head and the trochanters.
Synthetic thermoplastics that are tough, flexible, inert, and resistant to chemicals and electrical current. They are often used as biocompatible materials for prostheses and implants.
Inbred ICR mice are a strain of albino laboratory mice that have been selectively bred for consistent genetic makeup and high reproductive performance, making them widely used in biomedical research for studies involving reproduction, toxicology, pharmacology, and carcinogenesis.
Oral tissue surrounding and attached to TEETH.
Inflammation of the PERIAPICAL TISSUE. It includes general, unspecified, or acute nonsuppurative inflammation. Chronic nonsuppurative inflammation is PERIAPICAL GRANULOMA. Suppurative inflammation is PERIAPICAL ABSCESS.
Decalcification of bone or abnormal bone development due to chronic KIDNEY DISEASES, in which 1,25-DIHYDROXYVITAMIN D3 synthesis by the kidneys is impaired, leading to reduced negative feedback on PARATHYROID HORMONE. The resulting SECONDARY HYPERPARATHYROIDISM eventually leads to bone disorders.
Benign unilocular lytic areas in the proximal end of a long bone with well defined and narrow endosteal margins. The cysts contain fluid and the cyst walls may contain some giant cells. Bone cysts usually occur in males between the ages 3-15 years.
The properties, processes, and behavior of biological systems under the action of mechanical forces.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Two pairs of small oval-shaped glands located in the front and the base of the NECK and adjacent to the two lobes of THYROID GLAND. They secrete PARATHYROID HORMONE that regulates the balance of CALCIUM; PHOSPHORUS; and MAGNESIUM in the body.
Compounds containing 1,3-diazole, a five membered aromatic ring containing two nitrogen atoms separated by one of the carbons. Chemically reduced ones include IMIDAZOLINES and IMIDAZOLIDINES. Distinguish from 1,2-diazole (PYRAZOLES).
A bone tumor composed of cellular spindle-cell stroma containing scattered multinucleated giant cells resembling osteoclasts. The tumors range from benign to frankly malignant lesions. The tumor occurs most frequently in an end of a long tubular bone in young adults. (From Dorland, 27th ed; Stedman, 25th ed)
The physiological period following the MENOPAUSE, the permanent cessation of the menstrual life.
A non-vascular form of connective tissue composed of CHONDROCYTES embedded in a matrix that includes CHONDROITIN SULFATE and various types of FIBRILLAR COLLAGEN. There are three major types: HYALINE CARTILAGE; FIBROCARTILAGE; and ELASTIC CARTILAGE.
A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.
Malfunction of implantation shunts, valves, etc., and prosthesis loosening, migration, and breaking.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
The most common and most biologically active of the mammalian prostaglandins. It exhibits most biological activities characteristic of prostaglandins and has been used extensively as an oxytocic agent. The compound also displays a protective effect on the intestinal mucosa.
A vitamin that includes both CHOLECALCIFEROLS and ERGOCALCIFEROLS, which have the common effect of preventing or curing RICKETS in animals. It can also be viewed as a hormone since it can be formed in SKIN by action of ULTRAVIOLET RAYS upon the precursors, 7-dehydrocholesterol and ERGOSTEROL, and acts on VITAMIN D RECEPTORS to regulate CALCIUM in opposition to PARATHYROID HORMONE.
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)
The methyl esters of methacrylic acid that polymerize easily and are used as tissue cements, dental materials, and absorbent for biological substances.
Extraoral body-section radiography depicting an entire maxilla, or both maxilla and mandible, on a single film.
Dense fibrous layer formed from mesodermal tissue that surrounds the epithelial enamel organ. The cells eventually migrate to the external surface of the newly formed root dentin and give rise to the cementoblasts that deposit cementum on the developing root, fibroblasts of the developing periodontal ligament, and osteoblasts of the developing alveolar bone.
Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.
Receptors such as INTEGRIN ALPHAVBETA3 that bind VITRONECTIN with high affinity and play a role in cell migration. They also bind FIBRINOGEN; VON WILLEBRAND FACTOR; osteopontin; and THROMBOSPONDINS.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
A cytokine that stimulates the growth and differentiation of B-LYMPHOCYTES and is also a growth factor for HYBRIDOMAS and plasmacytomas. It is produced by many different cells including T-LYMPHOCYTES; MONOCYTES; and FIBROBLASTS.
Derivative of 7-dehydroxycholesterol formed by ULTRAVIOLET RAYS breaking of the C9-C10 bond. It differs from ERGOCALCIFEROL in having a single bond between C22 and C23 and lacking a methyl group at C24.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
A dark-gray, metallic element of widespread distribution but occurring in small amounts; atomic number, 22; atomic weight, 47.90; symbol, Ti; specific gravity, 4.5; used for fixation of fractures. (Dorland, 28th ed)
Serum glycoprotein produced by activated MACROPHAGES and other mammalian MONONUCLEAR LEUKOCYTES. It has necrotizing activity against tumor cell lines and increases ability to reject tumor transplants. Also known as TNF-alpha, it is only 30% homologous to TNF-beta (LYMPHOTOXIN), but they share TNF RECEPTORS.
Syndromes of bone destruction where the cause is not obvious such as neoplasia, infection, or trauma. The destruction follows various patterns: massive (Gorham disease), multicentric (HAJDU-CHENEY SYNDROME), or carpal/tarsal.
The surgical removal of a tooth. (Dorland, 28th ed)
The phase of orthodontics concerned with the correction of malocclusion with proper appliances and prevention of its sequelae (Jablonski's Illus. Dictionary of Dentistry).
The teeth of the first dentition, which are shed and replaced by the permanent teeth.
A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.
The shaft of long bones.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
A bone morphogenetic protein that is a potent inducer of BONE formation. It plays additional roles in regulating CELL DIFFERENTIATION of non-osteoblastic cell types and epithelial-mesenchymal interactions.
Inorganic salts of phosphoric acid.
Horizontal and, to a lesser degree, axial movement of a tooth in response to normal forces, as in occlusion. It refers also to the movability of a tooth resulting from loss of all or a portion of its attachment and supportive apparatus, as seen in periodontitis, occlusal trauma, and periodontosis. (From Jablonski, Dictionary of Dentistry, 1992, p507 & Boucher's Clinical Dental Terminology, 4th ed, p313)
Culture media containing biologically active components obtained from previously cultured cells or tissues that have released into the media substances affecting certain cell functions (e.g., growth, lysis).
The total absence of teeth from either the mandible or the maxilla, but not both. Total absence of teeth from both is MOUTH, EDENTULOUS. Partial absence of teeth in either is JAW, EDENTULOUS, PARTIALLY.
A condition of abnormally elevated output of PARATHYROID HORMONE (or PTH) triggering responses that increase blood CALCIUM. It is characterized by HYPERCALCEMIA and BONE RESORPTION, eventually leading to bone diseases. PRIMARY HYPERPARATHYROIDISM is caused by parathyroid HYPERPLASIA or PARATHYROID NEOPLASMS. SECONDARY HYPERPARATHYROIDISM is increased PTH secretion in response to HYPOCALCEMIA, usually caused by chronic KIDNEY DISEASES.
Reduction of the blood calcium below normal. Manifestations include hyperactive deep tendon reflexes, Chvostek's sign, muscle and abdominal cramps, and carpopedal spasm. (Dorland, 27th ed)
Established cell cultures that have the potential to propagate indefinitely.
Compounds that interact with ESTROGEN RECEPTORS in target tissues to bring about the effects similar to those of ESTRADIOL. Estrogens stimulate the female reproductive organs, and the development of secondary female SEX CHARACTERISTICS. Estrogenic chemicals include natural, synthetic, steroidal, or non-steroidal compounds.

Bone resorption induced by parathyroid hormone is strikingly diminished in collagenase-resistant mutant mice. (1/2466)

Parathyroid hormone (PTH) stimulates bone resorption by acting directly on osteoblasts/stromal cells and then indirectly to increase differentiation and function of osteoclasts. PTH acting on osteoblasts/stromal cells increases collagenase gene transcription and synthesis. To assess the role of collagenase in the bone resorptive actions of PTH, we used mice homozygous (r/r) for a targeted mutation (r) in Col1a1 that are resistant to collagenase cleavage of type I collagen. Human PTH(1-34) was injected subcutaneously over the hemicalvariae in wild-type (+/+) or r/r mice four times daily for three days. Osteoclast numbers, the size of the bone marrow spaces and periosteal proliferation were increased in calvariae from PTH-treated +/+ mice, whereas in r/r mice, PTH-induced bone resorption responses were minimal. The r/r mice were not resistant to other skeletal effects of PTH because abundant interstitial collagenase mRNA was detected in the calvarial periosteum of PTH-treated, but not vehicle-treated, r/r and +/+ mice. Calcemic responses, 0.5-10 hours after intraperitoneal injection of PTH, were blunted in r/r mice versus +/+ mice. Thus, collagenase cleavage of type I collagen is necessary for PTH induction of osteoclastic bone resorption.  (+info)

The development and structure of the chimpanzee mandible. (2/2466)

The sites of growth and remodeling, and the associated changes in cortical bone structure, have been studied in the chimpanzee mandible and compared with those previously reported in the human and macaque mandibles. The location of the principal sites of growth, and the distribution of the areas of deposition and resorption in the ramus, were found to be similar in all three species. In the chimpanzee, unlike Man, the bone being deposited at the condyle, posterior border of the ramus and coronoid process was plexiform in nature, indicating very rapid growth. The pattern of remodeling in the mandibular body, on the other hand, showed marked species differences at the chin and on the submandibular lingual surface, which account for the contrasts seen in the adult morphology of these regions. Although the pattern of distribution of cortical densities differed from that of surface remodeling, the information they give is complementary in analysing bone growth. The densest regions were found to coincide with sites of consistent lamellar deposition, while the least dense regions were those where plexiform bone was formed. Areas where remodeling led to the greatest reorientation of bone tissue within the cortex showed the greatest disparity between the two patterns.  (+info)

Ibandronate reduces osteolytic lesions but not tumor burden in a murine model of myeloma bone disease. (3/2466)

We determined the effects of the potent bisphosphonate ibandronate in a murine model of human myeloma bone disease. In this model, bone lesions typical of the human disease develop in mice following inoculation of myeloma cells via the tail vein. Treatment with ibandronate (4 micrograms per mouse per day) significantly reduced the occurrence of osteolytic bone lesions in myeloma-bearing mice. However, ibandronate did not prevent the mice from developing hindlimb paralysis and did not produce a detectable effect on survival. There was no significant effect of ibandronate on total myeloma cell burden, as assessed by morphometric measurements of myeloma cells in the bone marrow, liver, and spleen, or by measurement of serum IgG2b levels. These results support clinical findings that bisphosphonates may be useful for the treatment of myeloma-associated bone destruction, but suggest that other therapies are also required to reduce tumor growth.  (+info)

Study of the effect of lactational bone loss on blood lead concentrations in humans. (4/2466)

Lactation and other clinical states of high bone turnover have been suggested to release lead (Pb) stored in bone into blood and tissues. Previous observations on the influences of lactation have been anecdotal, or at high blood Pb concentrations with varying past exposures, or complicated by postpartum fluid changes. A prospective observational study was performed to investigate possible changes in blood lead concentrations at multiple intervals during lactation for 6 months postpartum and to relate changes in blood lead concentrations to changes in bone density and other variables. Volunteer pregnant subjects (n = 58) were enrolled from a midwifery service at an academic public health hospital. Subjects were mostly Hispanic, recently immigrated, of low economic status, not receiving supplemental calcium, and had low blood Pb concentrations (2.35 +/- 2.05 microg/dl at enrollment). Bone density losses over 6 months for the group averaged -2.46 +/- 6.33% at the vertebral spine and -0.67 +/- 5.21% at the femoral neck. In predicting final bone density, apart from initial bone density only the total number of breast-feedings was a significant independent variable of the variables tested, accounting for an additional 12% of the variability. No changes in blood Pb concentrations were seen over the interval beyond 2 weeks postpartum (minimum detectable change was 0.4 microg/dl). There was no relation between the changes in bone density and changes in blood Pb or the integrated blood Pb over the 2-week to 6-month period. Normal (nonlactating) bone resorption rates contribute a large fraction of the Pb in blood during low-exposure circumstances. However, during lactation the increase in bone resorptive processes is probably relatively small with a larger decrease in deposition accounting for net bone loss, as suggested by other investigations. Thus, concomitant release of Pb from bones of lactating subjects with low blood lead concentrations on this background of high normal resorption was not large enough for detection.  (+info)

Biochemical markers of bone turnover in breast cancer patients with bone metastases: a preliminary report. (5/2466)

BACKGROUND: Some biochemical markers of bone turnover are expected to reflect the disease activity of metastatic bone tumor. In the present study six biochemical markers were evaluated to determine appropriate markers for the detection of metastatic bone tumors from breast cancer (BC). METHODS: A panel of bone turnover markers was assessed in 11 normocalcemic patients with bone metastases from BC and in 19 BC patients without clinical evidence of bone metastases. Bone formation was investigated by measuring serum bone isoenzyme of alkaline phosphatase (BALP), osteocalcin (OC) and carboxy-terminal propeptide of type I procollagen (PICP): Bone resorption was investigated by measuring serum carboxy-terminal telopeptide of type I collagen (ICTP), fasting urinary pyridinoline (Pyr) and deoxypyridinoline (D-Pyr). RESULTS: PICP was influenced by age and menopausal status. Significant correlations were observed between each of bone turnover markers except between BALP and OC. The mean levels of the six bone turnover markers were higher in patients with bone metastases than in those without them and significance was observed except for OC. The best diagnostic efficiency by receiver-operating characteristic (ROC) analysis was provided by ICTP followed by Pyr or D-Pyr, BALP, PICP and OC and significance was observed between ICTP and OC. Multiple logistic regression analysis adjusted by age revealed that the only significant marker related to bone metastases was ICTP. CONCLUSIONS: Serum ICTP appears to be the leading marker of bone metastases from BC. However, to reveal the clinical usefulness of these markers, further examination will be needed to account for the ease and cost-effectiveness of the measurements.  (+info)

Acute fasting diminishes the circadian rhythm of biochemical markers of bone resorption. (6/2466)

OBJECTIVE: Biochemical markers of bone turnover exhibit circadian rhythms with the peak during the night/early morning and the nadir in the late afternoon. The nocturnal increase in bone resorption could theoretically be caused by the absence of food consumption which brings about a decrease in net calcium absorption and an increase in parathyroid hormone (PTH), followed by increased bone resorption in response to the body's demand for calcium. The aim of the present study was to assess the influence of a 33-h fast on the circadian variation in biochemical markers of bone turnover. DESIGN: Eleven healthy premenopausal women (age: 24+/-5 years) participated in a randomised, cross-over study consisting of two periods: either 33h of fasting (fasting) followed 1 week later by a 33-h period with regular meals eaten at 0800-0830h, 1130-1230h and 1800-1900h (control) or vice versa. METHODS: Urinary CrossLaps (U-CL/Cr) corrected with creatinine, as a marker of bone resorption; serum osteocalcin (sOC) as a marker of bone formation; serum intact PTH (iPTH); serum phosphate; and serum calcium corrected with albumin. RESULTS: Both the fasting and the control periods showed a significant circadian rhythm in U-CL/Cr (P<0.001), but the decrease was significantly less pronounced in the morning hours during the fasting period. Fasting resulted in a significant decrease in serum iPTH (throughout the study period) as compared with the control period (P<0.05-0.001). No change was observed in sOC by fasting. CONCLUSION: Food consumption has a small influence on the circadian variation in bone resorption, independent of PTH. The fall in iPTH during fasting may be secondary to an increased bone resorption produced by fasting.  (+info)

A prospective study of bone loss and turnover after allogeneic bone marrow transplantation: effect of calcium supplementation with or without calcitonin. (7/2466)

Transplantation of solid organs including heart, kidney, and liver is associated with rapid bone loss and increased rate of fracture; data on bone marrow transplantation recipients (BMT) are scarce. The purpose of the present study was to examine the magnitude, timing, and mechanism of bone loss following allogeneic BMT, and to study whether bone loss can be prevented by calcium with or without calcitonin. Sixty-nine patients undergoing allogeneic BMT for malignant blood diseases were enrolled into the study. Forty-four (22 women, 22 men) completed 6 months, and 36 patients 1 year follow-up. They were randomized to receive either no additional treatment (n = 22), or oral calcium 1 g twice daily for 12 months (n = 12) or the same dose of calcium plus intranasal calcitonin 400 IU/day for the first month and then 200 IU/day for 11 months (n = 10). Bone mineral density (BMD) at the lumbar spine and three femoral sites (femoral neck, trochanter, Ward's triangle) was measured by dual-energy X-ray absorptiometry (DXA). Bone turnover rate was followed with markers of bone formation and resorption (serum bone-specific alkaline phosphatase (B-ALP), type I procollagen carboxyterminal (PICP) and aminoterminal propeptide (PINP), serum type I collagen carboxyterminal telopeptide (ICTP)). Serum testosterone was assayed in men. Calcium with or without calcitonin had no effect on bone loss or bone markers; consequently the three study groups were combined. During the first 6 post-transplant months BMD decreased by 5.7% in the lumbar spine and by 6.9% to 8.7% in the three femoral sites (P < 0.0001 for all); no significant further decline occured between 6 and 12 months. Four out of 25 assessable patients experienced vertebral compression fractures. Markers of bone formation reduced: B-ALP by 20% at 3 weeks (P = 0.027), PICP by 40% (P < 0.0001) and PINP by 63% at 6 weeks (P < 0.0001), with a return to baseline by 6 months. The marker of bone resorption, serum ICTP was above normal throughout the whole observation period, with a peak at 6 weeks (77% above baseline, P < 0.0001). In male patients serum testosterone decreased reaching a nadir (57% below baseline) at 6 weeks (P = 0.0003). In conclusion, significant bone loss occurs after BMT. It results from imbalance between reduced bone formation and increased bone resorption; hypogonadism may be a contributing factor in men. Bone loss can not be prevented by calcium with or without calcitonin.  (+info)

An odyssey from breast to bone: multi-step control of mammary metastases and osteolysis by matrix metalloproteinases. (8/2466)

Development of metastases distant to the primary site of solid tumors marks late stages of tumor progression. Almost all malignant mammary tumors are carcinomas arising from the breast epithelium, but the morphological and molecular alterations in the mammary stroma surrounding the premalignant and the growing tumor contribute to its conversion into neoplastic tissue. Two parameters are critical for initiation of the metastatic process and access of tumor cells to the circulation. These are the ability of tumor cells to invade the basement membrane and the stroma, and the neovascularization of breast tumor tissue. A major site for development of distant metastases is the skeleton. After colonizing the bone, tumor cells promote a cascade of events leading to recruitment of osteoclasts and subsequent osteolytic bone destruction. A ubiquitous theme of neoplastic progression of breast tumors is the overproduction of matrix metalloproteinases. In this review, we summarize the recent insights into the functional consequences of matrix metalloproteinase expression and activation during malignant conversion in the breast, and after bone colonization. The current literature supports the hypothesis that matrix metalloproteinases play a key role in the metastatic expansion of most, if not all, mammary tumors and in the ensuing bone loss.  (+info)

Bone resorption is the process by which bone tissue is broken down and absorbed into the body. It is a normal part of bone remodeling, in which old or damaged bone tissue is removed and new tissue is formed. However, excessive bone resorption can lead to conditions such as osteoporosis, in which bones become weak and fragile due to a loss of density. This process is carried out by cells called osteoclasts, which break down the bone tissue and release minerals such as calcium into the bloodstream.

"Bone" is the hard, dense connective tissue that makes up the skeleton of vertebrate animals. It provides support and protection for the body's internal organs, and serves as a attachment site for muscles, tendons, and ligaments. Bone is composed of cells called osteoblasts and osteoclasts, which are responsible for bone formation and resorption, respectively, and an extracellular matrix made up of collagen fibers and mineral crystals.

Bones can be classified into two main types: compact bone and spongy bone. Compact bone is dense and hard, and makes up the outer layer of all bones and the shafts of long bones. Spongy bone is less dense and contains large spaces, and makes up the ends of long bones and the interior of flat and irregular bones.

The human body has 206 bones in total. They can be further classified into five categories based on their shape: long bones, short bones, flat bones, irregular bones, and sesamoid bones.

Osteoclasts are large, multinucleated cells that are primarily responsible for bone resorption, a process in which they break down and dissolve the mineralized matrix of bones. They are derived from monocyte-macrophage precursor cells of hematopoietic origin and play a crucial role in maintaining bone homeostasis by balancing bone formation and bone resorption.

Osteoclasts adhere to the bone surface and create an isolated microenvironment, called the "resorption lacuna," between their cell membrane and the bone surface. Here, they release hydrogen ions into the lacuna through a process called proton pumping, which lowers the pH and dissolves the mineral component of the bone matrix. Additionally, osteoclasts secrete proteolytic enzymes, such as cathepsin K, that degrade the organic components, like collagen, in the bone matrix.

An imbalance in osteoclast activity can lead to various bone diseases, including osteoporosis and Paget's disease, where excessive bone resorption results in weakened and fragile bones.

Bone remodeling is the normal and continuous process by which bone tissue is removed from the skeleton (a process called resorption) and new bone tissue is formed (a process called formation). This ongoing cycle allows bones to repair microdamage, adjust their size and shape in response to mechanical stress, and maintain mineral homeostasis. The cells responsible for bone resorption are osteoclasts, while the cells responsible for bone formation are osteoblasts. These two cell types work together to maintain the structural integrity and health of bones throughout an individual's life.

During bone remodeling, the process can be divided into several stages:

1. Activation: The initiation of bone remodeling is triggered by various factors such as microdamage, hormonal changes, or mechanical stress. This leads to the recruitment and activation of osteoclast precursor cells.
2. Resorption: Osteoclasts attach to the bone surface and create a sealed compartment called a resorption lacuna. They then secrete acid and enzymes that dissolve and digest the mineralized matrix, creating pits or cavities on the bone surface. This process helps remove old or damaged bone tissue and releases calcium and phosphate ions into the bloodstream.
3. Reversal: After resorption is complete, the osteoclasts undergo apoptosis (programmed cell death), and mononuclear cells called reversal cells appear on the resorbed surface. These cells prepare the bone surface for the next stage by cleaning up debris and releasing signals that attract osteoblast precursors.
4. Formation: Osteoblasts, derived from mesenchymal stem cells, migrate to the resorbed surface and begin producing a new organic matrix called osteoid. As the osteoid mineralizes, it forms a hard, calcified structure that gradually replaces the resorbed bone tissue. The osteoblasts may become embedded within this newly formed bone as they differentiate into osteocytes, which are mature bone cells responsible for maintaining bone homeostasis and responding to mechanical stress.
5. Mineralization: Over time, the newly formed bone continues to mineralize, becoming stronger and more dense. This process helps maintain the structural integrity of the skeleton and ensures adequate calcium storage.

Throughout this continuous cycle of bone remodeling, hormones, growth factors, and mechanical stress play crucial roles in regulating the balance between resorption and formation. Disruptions to this delicate equilibrium can lead to various bone diseases, such as osteoporosis, where excessive resorption results in weakened bones and increased fracture risk.

Root resorption is a process that occurs when the body's own cells, called odontoclasts, break down and destroy the hard tissue of the tooth root. This can occur as a result of various factors such as trauma, infection, or orthodontic treatment. In some cases, it may be a normal part of the tooth development and eruption process in children. However, excessive or pathological root resorption can lead to weakening and loss of the tooth. It is often asymptomatic and discovered during routine dental x-rays.

Bone density refers to the amount of bone mineral content (usually measured in grams) in a given volume of bone (usually measured in cubic centimeters). It is often used as an indicator of bone strength and fracture risk. Bone density is typically measured using dual-energy X-ray absorptiometry (DXA) scans, which provide a T-score that compares the patient's bone density to that of a young adult reference population. A T-score of -1 or above is considered normal, while a T-score between -1 and -2.5 indicates osteopenia (low bone mass), and a T-score below -2.5 indicates osteoporosis (porous bones). Regular exercise, adequate calcium and vitamin D intake, and medication (if necessary) can help maintain or improve bone density and prevent fractures.

REceptor Activator of NF-kB (RANK) Ligand is a type of protein that plays a crucial role in the immune system and bone metabolism. It belongs to the tumor necrosis factor (TNF) superfamily and is primarily produced by osteoblasts, which are cells responsible for bone formation.

RANK Ligand binds to its receptor RANK, which is found on the surface of osteoclasts, a type of cell involved in bone resorption or breakdown. The binding of RANK Ligand to RANK activates signaling pathways that promote the differentiation, activation, and survival of osteoclasts, thereby increasing bone resorption.

Abnormalities in the RANKL-RANK signaling pathway have been implicated in various bone diseases, such as osteoporosis, rheumatoid arthritis, and certain types of cancer that metastasize to bones. Therefore, targeting this pathway with therapeutic agents has emerged as a promising approach for the treatment of these conditions.

Bone development, also known as ossification, is the process by which bone tissue is formed and grows. This complex process involves several different types of cells, including osteoblasts, which produce new bone matrix, and osteoclasts, which break down and resorb existing bone tissue.

There are two main types of bone development: intramembranous and endochondral ossification. Intramembranous ossification occurs when bone tissue forms directly from connective tissue, while endochondral ossification involves the formation of a cartilage model that is later replaced by bone.

During fetal development, most bones develop through endochondral ossification, starting as a cartilage template that is gradually replaced by bone tissue. However, some bones, such as those in the skull and clavicles, develop through intramembranous ossification.

Bone development continues after birth, with new bone tissue being laid down and existing tissue being remodeled throughout life. This ongoing process helps to maintain the strength and integrity of the skeleton, allowing it to adapt to changing mechanical forces and repair any damage that may occur.

Osteoprotegerin (OPG) is a soluble decoy receptor for the receptor activator of nuclear factor kappa-B ligand (RANKL). It is a member of the tumor necrosis factor (TNF) receptor superfamily and plays a crucial role in regulating bone metabolism. By binding to RANKL, OPG prevents it from interacting with its signaling receptor RANK on the surface of osteoclast precursor cells, thereby inhibiting osteoclast differentiation, activation, and survival. This results in reduced bone resorption and increased bone mass.

In addition to its role in bone homeostasis, OPG has also been implicated in various physiological and pathological processes, including immune regulation, cancer progression, and cardiovascular disease.

Bone neoplasms are abnormal growths or tumors that develop in the bone. They can be benign (non-cancerous) or malignant (cancerous). Benign bone neoplasms do not spread to other parts of the body and are rarely a threat to life, although they may cause problems if they grow large enough to press on surrounding tissues or cause fractures. Malignant bone neoplasms, on the other hand, can invade and destroy nearby tissue and may spread (metastasize) to other parts of the body.

There are many different types of bone neoplasms, including:

1. Osteochondroma - a benign tumor that develops from cartilage and bone
2. Enchondroma - a benign tumor that forms in the cartilage that lines the inside of the bones
3. Chondrosarcoma - a malignant tumor that develops from cartilage
4. Osteosarcoma - a malignant tumor that develops from bone cells
5. Ewing sarcoma - a malignant tumor that develops in the bones or soft tissues around the bones
6. Giant cell tumor of bone - a benign or occasionally malignant tumor that develops from bone tissue
7. Fibrosarcoma - a malignant tumor that develops from fibrous tissue in the bone

The symptoms of bone neoplasms vary depending on the type, size, and location of the tumor. They may include pain, swelling, stiffness, fractures, or limited mobility. Treatment options depend on the type and stage of the tumor but may include surgery, radiation therapy, chemotherapy, or a combination of these treatments.

Osteoblasts are specialized bone-forming cells that are derived from mesenchymal stem cells. They play a crucial role in the process of bone formation and remodeling. Osteoblasts synthesize, secrete, and mineralize the organic matrix of bones, which is mainly composed of type I collagen.

These cells have receptors for various hormones and growth factors that regulate their activity, such as parathyroid hormone, vitamin D, and transforming growth factor-beta. When osteoblasts are not actively producing bone matrix, they can become trapped within the matrix they produce, where they differentiate into osteocytes, which are mature bone cells that play a role in maintaining bone structure and responding to mechanical stress.

Abnormalities in osteoblast function can lead to various bone diseases, such as osteoporosis, osteogenesis imperfecta, and Paget's disease of bone.

Diphosphonates are a class of medications that are used to treat bone diseases, such as osteoporosis and Paget's disease. They work by binding to the surface of bones and inhibiting the activity of bone-resorbing cells called osteoclasts. This helps to slow down the breakdown and loss of bone tissue, which can help to reduce the risk of fractures.

Diphosphonates are typically taken orally in the form of tablets, but some forms may be given by injection. Commonly prescribed diphosphonates include alendronate (Fosamax), risedronate (Actonel), and ibandronate (Boniva). Side effects of diphosphonates can include gastrointestinal symptoms such as nausea, heartburn, and abdominal pain. In rare cases, they may also cause esophageal ulcers or osteonecrosis of the jaw.

It is important to follow the instructions for taking diphosphonates carefully, as they must be taken on an empty stomach with a full glass of water and the patient must remain upright for at least 30 minutes after taking the medication to reduce the risk of esophageal irritation. Regular monitoring of bone density and kidney function is also recommended while taking these medications.

Osteogenesis is the process of bone formation or development. It involves the differentiation and maturation of osteoblasts, which are bone-forming cells that synthesize and deposit the organic matrix of bone tissue, composed mainly of type I collagen. This organic matrix later mineralizes to form the inorganic crystalline component of bone, primarily hydroxyapatite.

There are two primary types of osteogenesis: intramembranous and endochondral. Intramembranous osteogenesis occurs directly within connective tissue, where mesenchymal stem cells differentiate into osteoblasts and form bone tissue without an intervening cartilage template. This process is responsible for the formation of flat bones like the skull and clavicles.

Endochondral osteogenesis, on the other hand, involves the initial development of a cartilaginous model or template, which is later replaced by bone tissue. This process forms long bones, such as those in the limbs, and occurs through several stages involving chondrocyte proliferation, hypertrophy, and calcification, followed by invasion of blood vessels and osteoblasts to replace the cartilage with bone tissue.

Abnormalities in osteogenesis can lead to various skeletal disorders and diseases, such as osteogenesis imperfecta (brittle bone disease), achondroplasia (a form of dwarfism), and cleidocranial dysplasia (a disorder affecting skull and collarbone development).

Alveolar bone loss refers to the breakdown and resorption of the alveolar process of the jawbone, which is the part of the jaw that contains the sockets of the teeth. This type of bone loss is often caused by periodontal disease, a chronic inflammation of the gums and surrounding tissues that can lead to the destruction of the structures that support the teeth.

In advanced stages of periodontal disease, the alveolar bone can become severely damaged or destroyed, leading to tooth loss. Alveolar bone loss can also occur as a result of other conditions, such as osteoporosis, trauma, or tumors. Dental X-rays and other imaging techniques are often used to diagnose and monitor alveolar bone loss. Treatment may include deep cleaning of the teeth and gums, medications, surgery, or tooth extraction in severe cases.

Bone diseases is a broad term that refers to various medical conditions that affect the bones. These conditions can be categorized into several groups, including:

1. Developmental and congenital bone diseases: These are conditions that affect bone growth and development before or at birth. Examples include osteogenesis imperfecta (brittle bone disease), achondroplasia (dwarfism), and cleidocranial dysostosis.
2. Metabolic bone diseases: These are conditions that affect the body's ability to maintain healthy bones. They are often caused by hormonal imbalances, vitamin deficiencies, or problems with mineral metabolism. Examples include osteoporosis, osteomalacia, and Paget's disease of bone.
3. Inflammatory bone diseases: These are conditions that cause inflammation in the bones. They can be caused by infections, autoimmune disorders, or other medical conditions. Examples include osteomyelitis, rheumatoid arthritis, and ankylosing spondylitis.
4. Degenerative bone diseases: These are conditions that cause the bones to break down over time. They can be caused by aging, injury, or disease. Examples include osteoarthritis, avascular necrosis, and diffuse idiopathic skeletal hyperostosis (DISH).
5. Tumors and cancers of the bone: These are conditions that involve abnormal growths in the bones. They can be benign or malignant. Examples include osteosarcoma, chondrosarcoma, and Ewing sarcoma.
6. Fractures and injuries: While not strictly a "disease," fractures and injuries are common conditions that affect the bones. They can result from trauma, overuse, or weakened bones. Examples include stress fractures, compound fractures, and dislocations.

Overall, bone diseases can cause a wide range of symptoms, including pain, stiffness, deformity, and decreased mobility. Treatment for these conditions varies depending on the specific diagnosis but may include medication, surgery, physical therapy, or lifestyle changes.

Receptor Activator of Nuclear Factor-kappa B (RANK) is a type I transmembrane protein and a member of the tumor necrosis factor receptor superfamily. It plays a crucial role in the regulation of bone metabolism through the activation of osteoclasts, which are cells responsible for bone resorption.

When RANK binds to its ligand, RANKL (Receptor Activator of Nuclear Factor-kappa B Ligand), it triggers a series of intracellular signaling events that lead to the activation and differentiation of osteoclast precursors into mature osteoclasts. This process is essential for maintaining bone homeostasis, as excessive osteoclast activity can result in bone loss and diseases such as osteoporosis.

In addition to its role in bone metabolism, RANK has also been implicated in the regulation of immune responses, as it is involved in the activation and differentiation of dendritic cells and T cells. Dysregulation of RANK signaling has been associated with various pathological conditions, including autoimmune diseases and cancer.

Bone matrix refers to the non-cellular component of bone that provides structural support and functions as a reservoir for minerals, such as calcium and phosphate. It is made up of organic and inorganic components. The organic component consists mainly of type I collagen fibers, which provide flexibility and tensile strength to the bone. The inorganic component is primarily composed of hydroxyapatite crystals, which give bone its hardness and compressive strength. Bone matrix also contains other proteins, growth factors, and signaling molecules that regulate bone formation, remodeling, and repair.

Bone marrow cells are the types of cells found within the bone marrow, which is the spongy tissue inside certain bones in the body. The main function of bone marrow is to produce blood cells. There are two types of bone marrow: red and yellow. Red bone marrow is where most blood cell production takes place, while yellow bone marrow serves as a fat storage site.

The three main types of bone marrow cells are:

1. Hematopoietic stem cells (HSCs): These are immature cells that can differentiate into any type of blood cell, including red blood cells, white blood cells, and platelets. They have the ability to self-renew, meaning they can divide and create more hematopoietic stem cells.
2. Red blood cell progenitors: These are immature cells that will develop into mature red blood cells, also known as erythrocytes. Red blood cells carry oxygen from the lungs to the body's tissues and carbon dioxide back to the lungs.
3. Myeloid and lymphoid white blood cell progenitors: These are immature cells that will develop into various types of white blood cells, which play a crucial role in the body's immune system by fighting infections and diseases. Myeloid progenitors give rise to granulocytes (neutrophils, eosinophils, and basophils), monocytes, and megakaryocytes (which eventually become platelets). Lymphoid progenitors differentiate into B cells, T cells, and natural killer (NK) cells.

Bone marrow cells are essential for maintaining a healthy blood cell count and immune system function. Abnormalities in bone marrow cells can lead to various medical conditions, such as anemia, leukopenia, leukocytosis, thrombocytopenia, or thrombocytosis, depending on the specific type of blood cell affected. Additionally, bone marrow cells are often used in transplantation procedures to treat patients with certain types of cancer, such as leukemia and lymphoma, or other hematologic disorders.

Acid phosphatase is a type of enzyme that is found in various tissues and organs throughout the body, including the prostate gland, red blood cells, bone, liver, spleen, and kidneys. This enzyme plays a role in several biological processes, such as bone metabolism and the breakdown of molecules like nucleotides and proteins.

Acid phosphatase is classified based on its optimum pH level for activity. Acid phosphatases have an optimal activity at acidic pH levels (below 7.0), while alkaline phosphatases have an optimal activity at basic or alkaline pH levels (above 7.0).

In clinical settings, measuring the level of acid phosphatase in the blood can be useful as a tumor marker for prostate cancer. Elevated acid phosphatase levels may indicate the presence of metastatic prostate cancer or disease progression. However, it is important to note that acid phosphatase is not specific to prostate cancer and can also be elevated in other conditions, such as bone diseases, liver disorders, and some benign conditions. Therefore, acid phosphatase should be interpreted in conjunction with other diagnostic tests and clinical findings for a more accurate diagnosis.

Bone marrow is the spongy tissue found inside certain bones in the body, such as the hips, thighs, and vertebrae. It is responsible for producing blood-forming cells, including red blood cells, white blood cells, and platelets. There are two types of bone marrow: red marrow, which is involved in blood cell production, and yellow marrow, which contains fatty tissue.

Red bone marrow contains hematopoietic stem cells, which can differentiate into various types of blood cells. These stem cells continuously divide and mature to produce new blood cells that are released into the circulation. Red blood cells carry oxygen throughout the body, white blood cells help fight infections, and platelets play a crucial role in blood clotting.

Bone marrow also serves as a site for immune cell development and maturation. It contains various types of immune cells, such as lymphocytes, macrophages, and dendritic cells, which help protect the body against infections and diseases.

Abnormalities in bone marrow function can lead to several medical conditions, including anemia, leukopenia, thrombocytopenia, and various types of cancer, such as leukemia and multiple myeloma. Bone marrow aspiration and biopsy are common diagnostic procedures used to evaluate bone marrow health and function.

Fetal resorption, also known as fetal demise or intrauterine fetal death, is a medical term that refers to the absorption of a nonviable fetus by the mother's body after its death in utero. This process typically occurs before the 20th week of gestation and may go unnoticed if it happens early in pregnancy.

During fetal resorption, the fetal tissue is broken down and absorbed by the mother's body, leaving no visible remains of the fetus. The placenta and other surrounding tissues may still be present, but they often undergo changes as well. In some cases, a small amount of fetal tissue may be expelled from the uterus during the resorption process.

The causes of fetal resorption can vary, including chromosomal abnormalities, maternal health conditions, infections, and environmental factors. It is essential to seek medical attention if a woman suspects fetal resorption or experiences any unusual symptoms during pregnancy, such as vaginal bleeding or decreased fetal movement, to ensure proper diagnosis and management.

Osteoporosis is a systemic skeletal disease characterized by low bone mass, deterioration of bone tissue, and disruption of bone architecture, leading to increased risk of fractures, particularly in the spine, wrist, and hip. It mainly affects older people, especially postmenopausal women, due to hormonal changes that reduce bone density. Osteoporosis can also be caused by certain medications, medical conditions, or lifestyle factors such as smoking, alcohol abuse, and a lack of calcium and vitamin D in the diet. The diagnosis is often made using bone mineral density testing, and treatment may include medication to slow bone loss, promote bone formation, and prevent fractures.

Osteolysis is a medical term that refers to the loss or resorption of bone tissue. It's a process where the body's normal bone remodeling cycle is disrupted, leading to an imbalance between bone formation and bone breakdown. This results in the progressive deterioration and destruction of bone.

Osteolysis can occur due to various reasons such as chronic inflammation, mechanical stress, or certain medical conditions like rheumatoid arthritis, Paget's disease, or bone tumors. It can also be a side effect of some medications, such as those used in cancer treatment or for managing osteoporosis.

In severe cases, osteolysis can lead to weakened bones, increased risk of fractures, and deformities. Treatment typically aims to address the underlying cause and may include medication, surgery, or lifestyle changes.

The skull is the bony structure that encloses and protects the brain, the eyes, and the ears. It is composed of two main parts: the cranium, which contains the brain, and the facial bones. The cranium is made up of several fused flat bones, while the facial bones include the upper jaw (maxilla), lower jaw (mandible), cheekbones, nose bones, and eye sockets (orbits).

The skull also provides attachment points for various muscles that control chewing, moving the head, and facial expressions. Additionally, it contains openings for blood vessels, nerves, and the spinal cord to pass through. The skull's primary function is to protect the delicate and vital structures within it from injury and trauma.

Cathepsin K is a proteolytic enzyme, which belongs to the family of papain-like cysteine proteases. It is primarily produced by osteoclasts, which are specialized cells responsible for bone resorption. Cathepsin K plays a crucial role in the degradation and remodeling of the extracellular matrix, particularly in bone tissue.

This enzyme is capable of breaking down various proteins, including collagen, elastin, and proteoglycans, which are major components of the bone matrix. By doing so, cathepsin K helps osteoclasts to dissolve and remove mineralized and non-mineralized bone matrix during the process of bone resorption.

Apart from its function in bone metabolism, cathepsin K has also been implicated in several pathological conditions, such as osteoporosis, rheumatoid arthritis, and tumor metastasis to bones. Inhibitors of cathepsin K are being investigated as potential therapeutic agents for the treatment of these disorders.

Osteopetrosis, also known as Albers-Schönberg disease or marble bone disease, is a group of rare genetic disorders characterized by increased bone density due to impaired bone resorption by osteoclasts. This results in brittle bones that are more susceptible to fractures and can also lead to various complications such as anemia, hearing loss, and vision problems. There are several types of osteopetrosis, which vary in severity and age of onset.

The medical definition of osteopetrosis is:

A genetic disorder characterized by defective bone resorption due to impaired osteoclast function, resulting in increased bone density, susceptibility to fractures, and potential complications such as anemia, hearing loss, and vision problems.

Parathyroid hormone (PTH) is a polypeptide hormone that plays a crucial role in the regulation of calcium and phosphate levels in the body. It is produced and secreted by the parathyroid glands, which are four small endocrine glands located on the back surface of the thyroid gland.

The primary function of PTH is to maintain normal calcium levels in the blood by increasing calcium absorption from the gut, mobilizing calcium from bones, and decreasing calcium excretion by the kidneys. PTH also increases phosphate excretion by the kidneys, which helps to lower serum phosphate levels.

In addition to its role in calcium and phosphate homeostasis, PTH has been shown to have anabolic effects on bone tissue, stimulating bone formation and preventing bone loss. However, chronic elevations in PTH levels can lead to excessive bone resorption and osteoporosis.

Overall, Parathyroid Hormone is a critical hormone that helps maintain mineral homeostasis and supports healthy bone metabolism.

Alendronate is a medication that falls under the class of bisphosphonates. It is commonly used in the treatment and prevention of osteoporosis in postmenopausal women and men, as well as in the management of glucocorticoid-induced osteoporosis and Paget's disease of bone.

Alendronate works by inhibiting the activity of osteoclasts, which are cells responsible for breaking down and reabsorbing bone tissue. By reducing the activity of osteoclasts, alendronate helps to slow down bone loss and increase bone density, thereby reducing the risk of fractures.

The medication is available in several forms, including tablets and oral solutions, and is typically taken once a week for osteoporosis prevention and treatment. It is important to follow the dosing instructions carefully, as improper administration can reduce the drug's effectiveness or increase the risk of side effects. Common side effects of alendronate include gastrointestinal symptoms such as heartburn, stomach pain, and nausea.

Tooth resorption is a process in which there is an abnormal loss or breakdown of tooth structure, either internally (internal resorption) or externally (external resorption), due to the action of specialized cells called odontoclasts. This can lead to weakening and destruction of the tooth, potentially causing sensitivity, pain, or even tooth loss if left untreated. The causes of tooth resorption can vary, including trauma, orthodontic treatment, periodontal disease, and certain systemic conditions. It is important to diagnose and treat tooth resorption early to prevent further damage and preserve the tooth structure.

Metabolic bone diseases are a group of conditions that affect the bones and are caused by disorders in the body's metabolism. These disorders can result in changes to the bone structure, density, and strength, leading to an increased risk of fractures and other complications. Some common examples of metabolic bone diseases include:

1. Osteoporosis: a condition characterized by weak and brittle bones that are more likely to break, often as a result of age-related bone loss or hormonal changes.
2. Paget's disease of bone: a chronic disorder that causes abnormal bone growth and deformities, leading to fragile and enlarged bones.
3. Osteomalacia: a condition caused by a lack of vitamin D or problems with the body's ability to absorb it, resulting in weak and soft bones.
4. Hyperparathyroidism: a hormonal disorder that causes too much parathyroid hormone to be produced, leading to bone loss and other complications.
5. Hypoparathyroidism: a hormonal disorder that results in low levels of parathyroid hormone, causing weak and brittle bones.
6. Renal osteodystrophy: a group of bone disorders that occur as a result of chronic kidney disease, including osteomalacia, osteoporosis, and high turnover bone disease.

Treatment for metabolic bone diseases may include medications to improve bone density and strength, dietary changes, exercise, and lifestyle modifications. In some cases, surgery may be necessary to correct bone deformities or fractures.

The femur is the medical term for the thigh bone, which is the longest and strongest bone in the human body. It connects the hip bone to the knee joint and plays a crucial role in supporting the weight of the body and allowing movement during activities such as walking, running, and jumping. The femur is composed of a rounded head, a long shaft, and two condyles at the lower end that articulate with the tibia and patella to form the knee joint.

Osteocalcin is a protein that is produced by osteoblasts, which are the cells responsible for bone formation. It is one of the most abundant non-collagenous proteins found in bones and plays a crucial role in the regulation of bone metabolism. Osteocalcin contains a high affinity for calcium ions, making it essential for the mineralization of the bone matrix.

Once synthesized, osteocalcin is secreted into the extracellular matrix, where it binds to hydroxyapatite crystals, helping to regulate their growth and contributing to the overall strength and integrity of the bones. Osteocalcin also has been found to play a role in other physiological processes outside of bone metabolism, such as modulating insulin sensitivity, energy metabolism, and male fertility.

In summary, osteocalcin is a protein produced by osteoblasts that plays a critical role in bone formation, mineralization, and turnover, and has been implicated in various other physiological processes.

Bone regeneration is the biological process of new bone formation that occurs after an injury or removal of a portion of bone. This complex process involves several stages, including inflammation, migration and proliferation of cells, matrix deposition, and mineralization, leading to the restoration of the bone's structure and function.

The main cells involved in bone regeneration are osteoblasts, which produce new bone matrix, and osteoclasts, which resorb damaged or old bone tissue. The process is tightly regulated by various growth factors, hormones, and signaling molecules that promote the recruitment, differentiation, and activity of these cells.

Bone regeneration can occur naturally in response to injury or surgical intervention, such as fracture repair or dental implant placement. However, in some cases, bone regeneration may be impaired due to factors such as age, disease, or trauma, leading to delayed healing or non-union of the bone. In these situations, various strategies and techniques, including the use of bone grafts, scaffolds, and growth factors, can be employed to enhance and support the bone regeneration process.

Etidronic acid is a type of medication known as a bisphosphonate. It is used to treat conditions such as Paget's disease, osteoporosis, and certain types of cancer that have spread to the bones.

Etidronic acid works by inhibiting the activity of cells called osteoclasts, which are responsible for breaking down bone tissue. This helps to slow down the process of bone loss and can increase bone density, making bones stronger and less likely to break.

The medication is available in the form of a solution that is given intravenously (through a vein) in a hospital or clinic setting. It may be given as a single dose or as multiple doses over a period of time, depending on the condition being treated and the individual patient's needs.

As with any medication, etidronic acid can have side effects, including nausea, vomiting, diarrhea, and bone pain. It is important for patients to discuss the potential risks and benefits of this medication with their healthcare provider before starting treatment.

Collagen Type I is the most abundant form of collagen in the human body, found in various connective tissues such as tendons, ligaments, skin, and bones. It is a structural protein that provides strength and integrity to these tissues. Collagen Type I is composed of three alpha chains, two alpha-1(I) chains, and one alpha-2(I) chain, arranged in a triple helix structure. This type of collagen is often used in medical research and clinical applications, such as tissue engineering and regenerative medicine, due to its excellent mechanical properties and biocompatibility.

Calcitonin is a hormone that is produced and released by the parafollicular cells (also known as C cells) of the thyroid gland. It plays a crucial role in regulating calcium homeostasis in the body. Specifically, it helps to lower elevated levels of calcium in the blood by inhibiting the activity of osteoclasts, which are bone cells that break down bone tissue and release calcium into the bloodstream. Calcitonin also promotes the uptake of calcium in the bones and increases the excretion of calcium in the urine.

Calcitonin is typically released in response to high levels of calcium in the blood, and its effects help to bring calcium levels back into balance. In addition to its role in calcium regulation, calcitonin may also have other functions in the body, such as modulating immune function and reducing inflammation.

Clinically, synthetic forms of calcitonin are sometimes used as a medication to treat conditions related to abnormal calcium levels, such as hypercalcemia (high blood calcium) or osteoporosis. Calcitonin can be administered as an injection, nasal spray, or oral tablet, depending on the specific formulation and intended use.

Bone density conservation agents, also known as anti-resorptive agents or bone-sparing drugs, are a class of medications that help to prevent the loss of bone mass and reduce the risk of fractures. They work by inhibiting the activity of osteoclasts, the cells responsible for breaking down and reabsorbing bone tissue during the natural remodeling process.

Examples of bone density conservation agents include:

1. Bisphosphonates (e.g., alendronate, risedronate, ibandronate, zoledronic acid) - These are the most commonly prescribed class of bone density conservation agents. They bind to hydroxyapatite crystals in bone tissue and inhibit osteoclast activity, thereby reducing bone resorption.
2. Denosumab (Prolia) - This is a monoclonal antibody that targets RANKL (Receptor Activator of Nuclear Factor-κB Ligand), a key signaling molecule involved in osteoclast differentiation and activation. By inhibiting RANKL, denosumab reduces osteoclast activity and bone resorption.
3. Selective estrogen receptor modulators (SERMs) (e.g., raloxifene) - These medications act as estrogen agonists or antagonists in different tissues. In bone tissue, SERMs mimic the bone-preserving effects of estrogen by inhibiting osteoclast activity and reducing bone resorption.
4. Hormone replacement therapy (HRT) - Estrogen hormone replacement therapy has been shown to preserve bone density in postmenopausal women; however, its use is limited due to increased risks of breast cancer, cardiovascular disease, and thromboembolic events.
5. Calcitonin - This hormone, secreted by the thyroid gland, inhibits osteoclast activity and reduces bone resorption. However, it has largely been replaced by other more effective bone density conservation agents.

These medications are often prescribed for individuals at high risk of fractures due to conditions such as osteoporosis or metabolic disorders that affect bone health. It is essential to follow the recommended dosage and administration guidelines to maximize their benefits while minimizing potential side effects. Regular monitoring of bone density, blood calcium levels, and other relevant parameters is also necessary during treatment with these medications.

The tibia, also known as the shin bone, is the larger of the two bones in the lower leg and part of the knee joint. It supports most of the body's weight and is a major insertion point for muscles that flex the foot and bend the leg. The tibia articulates with the femur at the knee joint and with the fibula and talus bone at the ankle joint. Injuries to the tibia, such as fractures, are common in sports and other activities that put stress on the lower leg.

Postmenopausal osteoporosis is a specific type of osteoporosis that occurs in women after they have gone through menopause. It is defined as a skeletal disorder characterized by compromised bone strength, leading to an increased risk of fractures. In this condition, the decline in estrogen levels that occurs during menopause accelerates bone loss, resulting in a decrease in bone density and quality, which can lead to fragility fractures, particularly in the hips, wrists, and spine.

It's important to note that while postmenopausal osteoporosis is more common in women, men can also develop osteoporosis due to other factors such as aging, lifestyle choices, and medical conditions.

Bone transplantation, also known as bone grafting, is a surgical procedure in which bone or bone-like material is transferred from one part of the body to another or from one person to another. The graft may be composed of cortical (hard outer portion) bone, cancellous (spongy inner portion) bone, or a combination of both. It can be taken from different sites in the same individual (autograft), from another individual of the same species (allograft), or from an animal source (xenograft). The purpose of bone transplantation is to replace missing bone, provide structural support, and stimulate new bone growth. This procedure is commonly used in orthopedic, dental, and maxillofacial surgeries to repair bone defects caused by trauma, tumors, or congenital conditions.

Alkaline phosphatase (ALP) is an enzyme found in various body tissues, including the liver, bile ducts, digestive system, bones, and kidneys. It plays a role in breaking down proteins and minerals, such as phosphate, in the body.

The medical definition of alkaline phosphatase refers to its function as a hydrolase enzyme that removes phosphate groups from molecules at an alkaline pH level. In clinical settings, ALP is often measured through blood tests as a biomarker for various health conditions.

Elevated levels of ALP in the blood may indicate liver or bone diseases, such as hepatitis, cirrhosis, bone fractures, or cancer. Therefore, physicians may order an alkaline phosphatase test to help diagnose and monitor these conditions. However, it is essential to interpret ALP results in conjunction with other diagnostic tests and clinical findings for accurate diagnosis and treatment.

X-ray microtomography, often referred to as micro-CT, is a non-destructive imaging technique used to visualize and analyze the internal structure of objects with high spatial resolution. It is based on the principles of computed tomography (CT), where multiple X-ray images are acquired at different angles and then reconstructed into cross-sectional slices using specialized software. These slices can be further processed to create 3D visualizations, allowing researchers and clinicians to examine the internal structure and composition of samples in great detail. Micro-CT is widely used in materials science, biology, medicine, and engineering for various applications such as material characterization, bone analysis, and defect inspection.

Osteocytes are the most abundant cell type in mature bone tissue. They are star-shaped cells that are located inside the mineralized matrix of bones, with their processes extending into small spaces called lacunae and canaliculi. Osteocytes are derived from osteoblasts, which are bone-forming cells that become trapped within the matrix they produce.

Osteocytes play a crucial role in maintaining bone homeostasis by regulating bone remodeling, sensing mechanical stress, and modulating mineralization. They communicate with each other and with osteoblasts and osteoclasts (bone-resorbing cells) through a network of interconnected processes and via the release of signaling molecules. Osteocytes can also respond to changes in their environment, such as hormonal signals or mechanical loading, by altering their gene expression and releasing factors that regulate bone metabolism.

Dysfunction of osteocytes has been implicated in various bone diseases, including osteoporosis, osteogenesis imperfecta, and Paget's disease of bone.

Hypercalcemia is a medical condition characterized by an excess of calcium ( Ca2+ ) in the blood. While the normal range for serum calcium levels is typically between 8.5 to 10.2 mg/dL (milligrams per deciliter) or 2.14 to 2.55 mmol/L (millimoles per liter), hypercalcemia is generally defined as a serum calcium level greater than 10.5 mg/dL or 2.6 mmol/L.

Hypercalcemia can result from various underlying medical disorders, including primary hyperparathyroidism, malignancy (cancer), certain medications, granulomatous diseases, and excessive vitamin D intake or production. Symptoms of hypercalcemia may include fatigue, weakness, confusion, memory loss, depression, constipation, nausea, vomiting, increased thirst, frequent urination, bone pain, and kidney stones. Severe or prolonged hypercalcemia can lead to serious complications such as kidney failure, cardiac arrhythmias, and calcification of soft tissues. Treatment depends on the underlying cause and severity of the condition.

Tooth movement, in a dental and orthodontic context, refers to the physical change in position or alignment of one or more teeth within the jaw bone as a result of controlled forces applied through various orthodontic appliances such as braces, aligners, or other orthodontic devices. The purposeful manipulation of these forces encourages the periodontal ligament (the tissue that connects the tooth to the bone) to remodel, allowing the tooth to move gradually over time into the desired position. This process is crucial in achieving proper bite alignment, correcting malocclusions, and enhancing overall oral function and aesthetics.

Osteitis deformans, also known as Paget's disease of bone, is a chronic disorder of the bone characterized by abnormal turnover and remodeling of the bone. In this condition, the bone becomes enlarged, thickened, and deformed due to excessive and disorganized bone formation and resorption.

The process begins when the bone-remodeling cycle is disrupted, leading to an imbalance between the activity of osteoclasts (cells that break down bone) and osteoblasts (cells that form new bone). In Paget's disease, osteoclasts become overactive and increase bone resorption, followed by an overzealous response from osteoblasts, which attempt to repair the damage but do so in a disorganized manner.

The affected bones can become weakened, prone to fractures, and may cause pain, deformities, or other complications such as arthritis, hearing loss, or neurological symptoms if the skull or spine is involved. The exact cause of Paget's disease remains unknown, but it is believed that genetic and environmental factors play a role in its development.

Early diagnosis and treatment can help manage the symptoms and prevent complications associated with osteitis deformans. Treatment options include medications to slow down bone turnover, pain management, and orthopedic interventions when necessary.

Cell differentiation is the process by which a less specialized cell, or stem cell, becomes a more specialized cell type with specific functions and structures. This process involves changes in gene expression, which are regulated by various intracellular signaling pathways and transcription factors. Differentiation results in the development of distinct cell types that make up tissues and organs in multicellular organisms. It is a crucial aspect of embryonic development, tissue repair, and maintenance of homeostasis in the body.

A bone fracture is a medical condition in which there is a partial or complete break in the continuity of a bone due to external or internal forces. Fractures can occur in any bone in the body and can vary in severity from a small crack to a shattered bone. The symptoms of a bone fracture typically include pain, swelling, bruising, deformity, and difficulty moving the affected limb. Treatment for a bone fracture may involve immobilization with a cast or splint, surgery to realign and stabilize the bone, or medication to manage pain and prevent infection. The specific treatment approach will depend on the location, type, and severity of the fracture.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

Physiologic calcification is the normal deposit of calcium salts in body tissues and organs. It is a natural process that occurs as part of the growth and development of the human body, as well as during the repair and remodeling of tissues.

Calcium is an essential mineral that plays a critical role in many bodily functions, including bone formation, muscle contraction, nerve impulse transmission, and blood clotting. In order to maintain proper levels of calcium in the body, excess calcium that is not needed for these functions may be deposited in various tissues as a normal part of the aging process.

Physiologic calcification typically occurs in areas such as the walls of blood vessels, the lungs, and the heart valves. While these calcifications are generally harmless, they can sometimes lead to complications, particularly if they occur in large amounts or in sensitive areas. For example, calcification of the coronary arteries can increase the risk of heart disease, while calcification of the lung tissue can cause respiratory symptoms.

It is important to note that pathologic calcification, on the other hand, refers to the abnormal deposit of calcium salts in tissues and organs, which can be caused by various medical conditions such as chronic kidney disease, hyperparathyroidism, and certain infections. Pathologic calcification is not a normal process and can lead to serious health complications if left untreated.

The parietal bone is one of the four flat bones that form the skull's cranial vault, which protects the brain. There are two parietal bones in the skull, one on each side, located posterior to the frontal bone and temporal bone, and anterior to the occipital bone. Each parietal bone has a squamous part, which forms the roof and sides of the skull, and a smaller, wing-like portion called the mastoid process. The parietal bones contribute to the formation of the coronal and lambdoid sutures, which are fibrous joints that connect the bones in the skull.

Ovariectomy is a surgical procedure in which one or both ovaries are removed. It is also known as "ovary removal" or "oophorectomy." This procedure is often performed as a treatment for various medical conditions, including ovarian cancer, endometriosis, uterine fibroids, and pelvic pain. Ovariectomy can also be part of a larger surgical procedure called an hysterectomy, in which the uterus is also removed.

In some cases, an ovariectomy may be performed as a preventative measure for individuals at high risk of developing ovarian cancer. This is known as a prophylactic ovariectomy. After an ovariectomy, a person will no longer have menstrual periods and will be unable to become pregnant naturally. Hormone replacement therapy may be recommended in some cases to help manage symptoms associated with the loss of hormones produced by the ovaries.

The alveolar process is the curved part of the jawbone (mandible or maxilla) that contains sockets or hollow spaces (alveoli) for the teeth to be embedded. These processes are covered with a specialized mucous membrane called the gingiva, which forms a tight seal around the teeth to help protect the periodontal tissues and maintain oral health.

The alveolar process is composed of both compact and spongy bone tissue. The compact bone forms the outer layer, while the spongy bone is found inside the alveoli and provides support for the teeth. When a tooth is lost or extracted, the alveolar process begins to resorb over time due to the lack of mechanical stimulation from the tooth's chewing forces. This can lead to changes in the shape and size of the jawbone, which may require bone grafting procedures before dental implant placement.

Hydroxyproline is not a medical term per se, but it is a significant component in the medical field, particularly in the study of connective tissues and collagen. Here's a scientific definition:

Hydroxyproline is a modified amino acid that is formed by the post-translational modification of the amino acid proline in collagen and some other proteins. This process involves the addition of a hydroxyl group (-OH) to the proline residue, which alters its chemical properties and contributes to the stability and structure of collagen fibers. Collagen is the most abundant protein in the human body and is a crucial component of connective tissues such as tendons, ligaments, skin, and bones. The presence and quantity of hydroxyproline can serve as a marker for collagen turnover and degradation, making it relevant to various medical and research contexts, including the study of diseases affecting connective tissues like osteoarthritis, rheumatoid arthritis, and Ehlers-Danlos syndrome.

Calcium is an essential mineral that is vital for various physiological processes in the human body. The medical definition of calcium is as follows:

Calcium (Ca2+) is a crucial cation and the most abundant mineral in the human body, with approximately 99% of it found in bones and teeth. It plays a vital role in maintaining structural integrity, nerve impulse transmission, muscle contraction, hormonal secretion, blood coagulation, and enzyme activation.

Calcium homeostasis is tightly regulated through the interplay of several hormones, including parathyroid hormone (PTH), calcitonin, and vitamin D. Dietary calcium intake, absorption, and excretion are also critical factors in maintaining optimal calcium levels in the body.

Hypocalcemia refers to low serum calcium levels, while hypercalcemia indicates high serum calcium levels. Both conditions can have detrimental effects on various organ systems and require medical intervention to correct.

A biological marker, often referred to as a biomarker, is a measurable indicator that reflects the presence or severity of a disease state, or a response to a therapeutic intervention. Biomarkers can be found in various materials such as blood, tissues, or bodily fluids, and they can take many forms, including molecular, histologic, radiographic, or physiological measurements.

In the context of medical research and clinical practice, biomarkers are used for a variety of purposes, such as:

1. Diagnosis: Biomarkers can help diagnose a disease by indicating the presence or absence of a particular condition. For example, prostate-specific antigen (PSA) is a biomarker used to detect prostate cancer.
2. Monitoring: Biomarkers can be used to monitor the progression or regression of a disease over time. For instance, hemoglobin A1c (HbA1c) levels are monitored in diabetes patients to assess long-term blood glucose control.
3. Predicting: Biomarkers can help predict the likelihood of developing a particular disease or the risk of a negative outcome. For example, the presence of certain genetic mutations can indicate an increased risk for breast cancer.
4. Response to treatment: Biomarkers can be used to evaluate the effectiveness of a specific treatment by measuring changes in the biomarker levels before and after the intervention. This is particularly useful in personalized medicine, where treatments are tailored to individual patients based on their unique biomarker profiles.

It's important to note that for a biomarker to be considered clinically valid and useful, it must undergo rigorous validation through well-designed studies, including demonstrating sensitivity, specificity, reproducibility, and clinical relevance.

Bone marrow transplantation (BMT) is a medical procedure in which damaged or destroyed bone marrow is replaced with healthy bone marrow from a donor. Bone marrow is the spongy tissue inside bones that produces blood cells. The main types of BMT are autologous, allogeneic, and umbilical cord blood transplantation.

In autologous BMT, the patient's own bone marrow is used for the transplant. This type of BMT is often used in patients with lymphoma or multiple myeloma who have undergone high-dose chemotherapy or radiation therapy to destroy their cancerous bone marrow.

In allogeneic BMT, bone marrow from a genetically matched donor is used for the transplant. This type of BMT is often used in patients with leukemia, lymphoma, or other blood disorders who have failed other treatments.

Umbilical cord blood transplantation involves using stem cells from umbilical cord blood as a source of healthy bone marrow. This type of BMT is often used in children and adults who do not have a matched donor for allogeneic BMT.

The process of BMT typically involves several steps, including harvesting the bone marrow or stem cells from the donor, conditioning the patient's body to receive the new bone marrow or stem cells, transplanting the new bone marrow or stem cells into the patient's body, and monitoring the patient for signs of engraftment and complications.

BMT is a complex and potentially risky procedure that requires careful planning, preparation, and follow-up care. However, it can be a life-saving treatment for many patients with blood disorders or cancer.

Bone substitutes are materials that are used to replace missing or damaged bone in the body. They can be made from a variety of materials, including natural bone from other parts of the body or from animals, synthetic materials, or a combination of both. The goal of using bone substitutes is to provide structural support and promote the growth of new bone tissue.

Bone substitutes are often used in dental, orthopedic, and craniofacial surgery to help repair defects caused by trauma, tumors, or congenital abnormalities. They can also be used to augment bone volume in procedures such as spinal fusion or joint replacement.

There are several types of bone substitutes available, including:

1. Autografts: Bone taken from another part of the patient's body, such as the hip or pelvis.
2. Allografts: Bone taken from a deceased donor and processed to remove any cells and infectious materials.
3. Xenografts: Bone from an animal source, typically bovine or porcine, that has been processed to remove any cells and infectious materials.
4. Synthetic bone substitutes: Materials such as calcium phosphate ceramics, bioactive glass, and polymer-based materials that are designed to mimic the properties of natural bone.

The choice of bone substitute material depends on several factors, including the size and location of the defect, the patient's medical history, and the surgeon's preference. It is important to note that while bone substitutes can provide structural support and promote new bone growth, they may not have the same strength or durability as natural bone. Therefore, they may not be suitable for all applications, particularly those that require high load-bearing capacity.

Macrophage Colony-Stimulating Factor (M-CSF) is a growth factor that belongs to the family of colony-stimulating factors (CSFs). It is a glycoprotein hormone that plays a crucial role in the survival, proliferation, and differentiation of mononuclear phagocytes, including macrophages. M-CSF binds to its receptor, CSF1R, which is expressed on the surface of monocytes, macrophages, and their precursors.

M-CSF stimulates the production of mature macrophages from monocyte precursors in the bone marrow and enhances the survival and function of mature macrophages in peripheral tissues. It also promotes the activation of macrophages, increasing their ability to phagocytize and destroy foreign particles, microorganisms, and tumor cells.

In addition to its role in the immune system, M-CSF has been implicated in various physiological processes, including hematopoiesis, bone remodeling, angiogenesis, and female reproduction. Dysregulation of M-CSF signaling has been associated with several pathological conditions, such as inflammatory diseases, autoimmune disorders, and cancer.

The ilium is the largest and broadest of the three parts that make up the hip bone or coxal bone. It is the uppermost portion of the pelvis and forms the side of the waist. The ilium has a curved, fan-like shape and articulates with the sacrum at the back to form the sacroiliac joint. The large, concave surface on the top of the ilium is called the iliac crest, which can be felt as a prominent ridge extending from the front of the hip to the lower back. This region is significant in orthopedics and physical examinations for its use in assessing various medical conditions and performing certain maneuvers during the physical examination.

Bone Morphogenetic Proteins (BMPs) are a group of growth factors that play crucial roles in the development, growth, and repair of bones and other tissues. They belong to the Transforming Growth Factor-β (TGF-β) superfamily and were first discovered when researchers found that certain proteins extracted from demineralized bone matrix had the ability to induce new bone formation.

BMPs stimulate the differentiation of mesenchymal stem cells into osteoblasts, which are the cells responsible for bone formation. They also promote the recruitment and proliferation of these cells, enhancing the overall process of bone regeneration. In addition to their role in bone biology, BMPs have been implicated in various other biological processes, including embryonic development, wound healing, and the regulation of fat metabolism.

There are several types of BMPs (BMP-2, BMP-4, BMP-7, etc.) that exhibit distinct functions and expression patterns. Due to their ability to stimulate bone formation, recombinant human BMPs have been used in clinical applications, such as spinal fusion surgery and non-healing fracture treatment. However, the use of BMPs in medicine has been associated with certain risks and complications, including uncontrolled bone growth, inflammation, and cancer development, which necessitates further research to optimize their therapeutic potential.

Calcitriol is the active form of vitamin D, also known as 1,25-dihydroxyvitamin D. It is a steroid hormone that plays a crucial role in regulating calcium and phosphate levels in the body to maintain healthy bones. Calcitriol is produced in the kidneys from its precursor, calcidiol (25-hydroxyvitamin D), which is derived from dietary sources or synthesized in the skin upon exposure to sunlight.

Calcitriol promotes calcium absorption in the intestines, helps regulate calcium and phosphate levels in the kidneys, and stimulates bone cells (osteoblasts) to form new bone tissue while inhibiting the activity of osteoclasts, which resorb bone. This hormone is essential for normal bone mineralization and growth, as well as for preventing hypocalcemia (low calcium levels).

In addition to its role in bone health, calcitriol has various other physiological functions, including modulating immune responses, cell proliferation, differentiation, and apoptosis. Calcitriol deficiency or resistance can lead to conditions such as rickets in children and osteomalacia or osteoporosis in adults.

Photon Absorptiometry is a medical technique used to measure the absorption of photons (light particles) by tissues or materials. In clinical practice, it is often used as a non-invasive method for measuring bone mineral density (BMD). This technique uses a low-energy X-ray beam or gamma ray to penetrate the tissue and then measures the amount of radiation absorbed by the bone. The amount of absorption is related to the density and thickness of the bone, allowing for an assessment of BMD. It can be used to diagnose osteoporosis and monitor treatment response in patients with bone diseases. There are two types of photon absorptiometry: single-photon absorptiometry (SPA) and dual-photon absorptiometry (DPA). SPA uses one energy level, while DPA uses two different energy levels to measure BMD, providing more precise measurements.

Clodronic acid is a medication that belongs to a class of drugs called bisphosphonates. It is used to treat and prevent osteoporosis in postmenopausal women and men with a high risk of fracture, as well as to treat Paget's disease of bone.

Clodronic acid works by inhibiting the activity of bone-resorbing cells called osteoclasts, which helps to slow down bone loss and increase bone density. This can help reduce the risk of fractures in people with osteoporosis.

The medication is available in several forms, including tablets and intravenous solutions. It is usually taken or administered once a day or once a week, depending on the specific formulation and the individual patient's needs.

Like all medications, clodronic acid can have side effects, including gastrointestinal symptoms such as nausea, vomiting, and diarrhea, as well as muscle pain, joint pain, and headaches. In rare cases, it can also cause more serious side effects such as esophageal ulcers and bone necrosis of the jaw. It is important for patients to follow their doctor's instructions carefully when taking this medication and to report any unusual symptoms or side effects promptly.

Bone cements are medical-grade materials used in orthopedic and trauma surgery to fill gaps between bone surfaces and implants, such as artificial joints or screws. They serve to mechanically stabilize the implant and provide a smooth, load-bearing surface. The two most common types of bone cement are:

1. Polymethylmethacrylate (PMMA) cement: This is a two-component system consisting of powdered PMMA and liquid methyl methacrylate monomer. When mixed together, they form a dough-like consistency that hardens upon exposure to air. PMMA cement has been widely used for decades in joint replacement surgeries, such as hip or knee replacements.
2. Calcium phosphate (CP) cement: This is a two-component system consisting of a powdered CP compound and an aqueous solution. When mixed together, they form a paste that hardens through a chemical reaction at body temperature. CP cement has lower mechanical strength compared to PMMA but demonstrates better biocompatibility, bioactivity, and the ability to resorb over time.

Both types of bone cements have advantages and disadvantages, and their use depends on the specific surgical indication and patient factors.

Collagen is the most abundant protein in the human body, and it is a major component of connective tissues such as tendons, ligaments, skin, and bones. Collagen provides structure and strength to these tissues and helps them to withstand stretching and tension. It is made up of long chains of amino acids, primarily glycine, proline, and hydroxyproline, which are arranged in a triple helix structure. There are at least 16 different types of collagen found in the body, each with slightly different structures and functions. Collagen is important for maintaining the integrity and health of tissues throughout the body, and it has been studied for its potential therapeutic uses in various medical conditions.

The periosteum is a highly vascularized and innervated tissue that surrounds the outer surface of bones, except at the articular surfaces. It consists of two layers: an outer fibrous layer containing blood vessels, nerves, and fibroblasts; and an inner cellular layer called the cambium or osteogenic layer, which contains progenitor cells capable of bone formation and repair.

The periosteum plays a crucial role in bone growth, remodeling, and healing by providing a source of osteoprogenitor cells and blood supply. It also contributes to the sensation of pain in response to injury or inflammation of the bone. Additionally, the periosteum can respond to mechanical stress by activating bone formation, making it an essential component in orthopedic treatments such as distraction osteogenesis.

Parathyroid Hormone-Related Protein (PTHrP) is a protein that is encoded by the PTHLH gene in humans. It is structurally similar to parathyroid hormone (PTH) and was initially identified due to its role in humoral hypercalcemia of malignancy, a condition characterized by high levels of calcium in the blood caused by certain types of cancer.

PTHrP has a variety of functions in the body, including regulation of calcium and phosphate homeostasis, cell growth and differentiation, and bone metabolism. It acts through a specific G protein-coupled receptor called the PTH/PTHrP receptor, which is found in many tissues throughout the body, including bone, kidney, and cartilage.

In contrast to PTH, which is primarily produced by the parathyroid glands and regulates calcium levels in the blood, PTHrP is produced by many different types of cells throughout the body. Its expression is regulated in a tissue-specific manner, and its functions can vary depending on the context in which it is produced.

Overall, PTHrP plays important roles in normal physiology as well as in various disease states, including cancer, bone disorders, and developmental abnormalities.

Phosphorus is an essential mineral that is required by every cell in the body for normal functioning. It is a key component of several important biomolecules, including adenosine triphosphate (ATP), which is the primary source of energy for cells, and deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), which are the genetic materials in cells.

Phosphorus is also a major constituent of bones and teeth, where it combines with calcium to provide strength and structure. In addition, phosphorus plays a critical role in various metabolic processes, including energy production, nerve impulse transmission, and pH regulation.

The medical definition of phosphorus refers to the chemical element with the atomic number 15 and the symbol P. It is a highly reactive non-metal that exists in several forms, including white phosphorus, red phosphorus, and black phosphorus. In the body, phosphorus is primarily found in the form of organic compounds, such as phospholipids, phosphoproteins, and nucleic acids.

Abnormal levels of phosphorus in the body can lead to various health problems. For example, high levels of phosphorus (hyperphosphatemia) can occur in patients with kidney disease or those who consume large amounts of phosphorus-rich foods, and can contribute to the development of calcification of soft tissues and cardiovascular disease. On the other hand, low levels of phosphorus (hypophosphatemia) can occur in patients with malnutrition, vitamin D deficiency, or alcoholism, and can lead to muscle weakness, bone pain, and an increased risk of infection.

Bone Morphogenetic Protein 2 (BMP-2) is a growth factor that belongs to the transforming growth factor-beta (TGF-β) superfamily. It plays a crucial role in bone and cartilage formation, as well as in the regulation of wound healing and embryonic development. BMP-2 stimulates the differentiation of mesenchymal stem cells into osteoblasts, which are cells responsible for bone formation.

BMP-2 has been approved by the US Food and Drug Administration (FDA) as a medical device to promote bone growth in certain spinal fusion surgeries and in the treatment of open fractures that have not healed properly. It is usually administered in the form of a collagen sponge soaked with recombinant human BMP-2 protein, which is a laboratory-produced version of the natural protein.

While BMP-2 has shown promising results in some clinical applications, its use is not without risks and controversies. Some studies have reported adverse effects such as inflammation, ectopic bone formation, and increased rates of cancer, which have raised concerns about its safety and efficacy. Therefore, it is essential to weigh the benefits and risks of BMP-2 therapy on a case-by-case basis and under the guidance of a qualified healthcare professional.

Periodontitis is a severe form of gum disease that damages the soft tissue and destroys the bone supporting your teeth. If left untreated, it can lead to tooth loss. It is caused by the buildup of plaque, a sticky film of bacteria that constantly forms on our teeth. The body's immune system fights the bacterial infection, which causes an inflammatory response. If the inflammation continues for a long time, it can damage the tissues and bones that support the teeth.

The early stage of periodontitis is called gingivitis, which is characterized by red, swollen gums that bleed easily when brushed or flossed. When gingivitis is not treated, it can advance to periodontitis. In addition to plaque, other factors that increase the risk of developing periodontitis include smoking or using tobacco products, poor oral hygiene, diabetes, a weakened immune system, and genetic factors.

Regular dental checkups and good oral hygiene practices, such as brushing twice a day, flossing daily, and using an antimicrobial mouth rinse, can help prevent periodontitis. Treatment for periodontitis may include deep cleaning procedures, medications, or surgery in severe cases.

C57BL/6 (C57 Black 6) is an inbred strain of laboratory mouse that is widely used in biomedical research. The term "inbred" refers to a strain of animals where matings have been carried out between siblings or other closely related individuals for many generations, resulting in a population that is highly homozygous at most genetic loci.

The C57BL/6 strain was established in 1920 by crossing a female mouse from the dilute brown (DBA) strain with a male mouse from the black strain. The resulting offspring were then interbred for many generations to create the inbred C57BL/6 strain.

C57BL/6 mice are known for their robust health, longevity, and ease of handling, making them a popular choice for researchers. They have been used in a wide range of biomedical research areas, including studies of cancer, immunology, neuroscience, cardiovascular disease, and metabolism.

One of the most notable features of the C57BL/6 strain is its sensitivity to certain genetic modifications, such as the introduction of mutations that lead to obesity or impaired glucose tolerance. This has made it a valuable tool for studying the genetic basis of complex diseases and traits.

Overall, the C57BL/6 inbred mouse strain is an important model organism in biomedical research, providing a valuable resource for understanding the genetic and molecular mechanisms underlying human health and disease.

Tooth eruption is the process by which a tooth emerges from the gums and becomes visible in the oral cavity. It is a normal part of dental development that occurs in a predictable sequence and timeframe. Primary or deciduous teeth, also known as baby teeth, begin to erupt around 6 months of age and continue to emerge until approximately 2-3 years of age. Permanent or adult teeth start to erupt around 6 years of age and can continue to emerge until the early twenties.

The process of tooth eruption involves several stages, including the formation of the tooth within the jawbone, the movement of the tooth through the bone and surrounding tissues, and the final emergence of the tooth into the mouth. Proper tooth eruption is essential for normal oral function, including chewing, speaking, and smiling. Any abnormalities in the tooth eruption process, such as delayed or premature eruption, can indicate underlying dental or medical conditions that require further evaluation and treatment.

Isoenzymes, also known as isoforms, are multiple forms of an enzyme that catalyze the same chemical reaction but differ in their amino acid sequence, structure, and/or kinetic properties. They are encoded by different genes or alternative splicing of the same gene. Isoenzymes can be found in various tissues and organs, and they play a crucial role in biological processes such as metabolism, detoxification, and cell signaling. Measurement of isoenzyme levels in body fluids (such as blood) can provide valuable diagnostic information for certain medical conditions, including tissue damage, inflammation, and various diseases.

Peptides are short chains of amino acid residues linked by covalent bonds, known as peptide bonds. They are formed when two or more amino acids are joined together through a condensation reaction, which results in the elimination of a water molecule and the formation of an amide bond between the carboxyl group of one amino acid and the amino group of another.

Peptides can vary in length from two to about fifty amino acids, and they are often classified based on their size. For example, dipeptides contain two amino acids, tripeptides contain three, and so on. Oligopeptides typically contain up to ten amino acids, while polypeptides can contain dozens or even hundreds of amino acids.

Peptides play many important roles in the body, including serving as hormones, neurotransmitters, enzymes, and antibiotics. They are also used in medical research and therapeutic applications, such as drug delivery and tissue engineering.

Tartrates are salts or esters of tartaric acid, a naturally occurring organic acid found in many fruits, particularly grapes. In a medical context, potassium bitartrate (also known as cream of tartar) is sometimes used as a mild laxative or to treat acidosis by helping to restore the body's normal pH balance. Additionally, sodium tartrate has been historically used as an antidote for lead poisoning. However, these uses are not common in modern medicine.

The mandible, also known as the lower jaw, is the largest and strongest bone in the human face. It forms the lower portion of the oral cavity and plays a crucial role in various functions such as mastication (chewing), speaking, and swallowing. The mandible is a U-shaped bone that consists of a horizontal part called the body and two vertical parts called rami.

The mandible articulates with the skull at the temporomandibular joints (TMJs) located in front of each ear, allowing for movements like opening and closing the mouth, protrusion, retraction, and side-to-side movement. The mandible contains the lower teeth sockets called alveolar processes, which hold the lower teeth in place.

In medical terminology, the term "mandible" refers specifically to this bone and its associated structures.

The maxilla is a paired bone that forms the upper jaw in vertebrates. In humans, it is a major bone in the face and plays several important roles in the craniofacial complex. Each maxilla consists of a body and four processes: frontal process, zygomatic process, alveolar process, and palatine process.

The maxillae contribute to the formation of the eye sockets (orbits), nasal cavity, and the hard palate of the mouth. They also contain the upper teeth sockets (alveoli) and help form the lower part of the orbit and the cheekbones (zygomatic arches).

Here's a quick rundown of its key functions:

1. Supports the upper teeth and forms the upper jaw.
2. Contributes to the formation of the eye sockets, nasal cavity, and hard palate.
3. Helps shape the lower part of the orbit and cheekbones.
4. Partakes in the creation of important sinuses, such as the maxillary sinus, which is located within the body of the maxilla.

Tumor Necrosis Factor (TNF) Receptors are cell surface receptors that bind to tumor necrosis factor cytokines. They play crucial roles in the regulation of a variety of immune cell functions, including inflammation, immunity, and cell survival or death (apoptosis).

There are two major types of TNF receptors: TNFR1 (also known as p55 or CD120a) and TNFR2 (also known as p75 or CD120b). TNFR1 is widely expressed in most tissues, while TNFR2 has a more restricted expression pattern and is mainly found on immune cells.

TNF receptors have an intracellular domain called the death domain, which can trigger signaling pathways leading to apoptosis when activated by TNF ligands. However, they can also activate other signaling pathways that promote cell survival, differentiation, and inflammation. Dysregulation of TNF receptor signaling has been implicated in various diseases, including cancer, autoimmune disorders, and neurodegenerative conditions.

Cathepsins are a type of proteolytic enzymes, which are found in lysosomes and are responsible for breaking down proteins inside the cell. They are classified as papain-like cysteine proteases and play important roles in various physiological processes, including tissue remodeling, antigen presentation, and apoptosis (programmed cell death). There are several different types of cathepsins, including cathepsin B, C, D, F, H, K, L, S, V, and X/Z, each with distinct substrate specificities and functions.

Dysregulation of cathepsins has been implicated in various pathological conditions, such as cancer, neurodegenerative diseases, and inflammatory disorders. For example, overexpression or hyperactivation of certain cathepsins has been shown to contribute to tumor invasion and metastasis, while their inhibition has been explored as a potential therapeutic strategy in cancer treatment. Similarly, abnormal levels of cathepsins have been linked to the progression of neurodegenerative diseases like Alzheimer's and Parkinson's, making them attractive targets for drug development.

Vacuolar Proton-Translocating ATPases (V-ATPases) are complex enzyme systems that are found in the membranes of various intracellular organelles, such as vacuoles, endosomes, lysosomes, and Golgi apparatus. They play a crucial role in the establishment and maintenance of electrochemical gradients across these membranes by actively pumping protons (H+) from the cytosol to the lumen of the organelles.

The V-ATPases are composed of two major components: a catalytic domain, known as V1, which contains multiple subunits and is responsible for ATP hydrolysis; and a membrane-bound domain, called V0, which consists of several subunits and facilitates proton translocation. The energy generated from ATP hydrolysis in the V1 domain is used to drive conformational changes in the V0 domain, resulting in the vectorial transport of protons across the membrane.

These electrochemical gradients established by V-ATPases are essential for various cellular processes, including secondary active transport, maintenance of organellar pH, protein sorting and trafficking, and regulation of cell volume. Dysfunction in V-ATPases has been implicated in several human diseases, such as neurodegenerative disorders, renal tubular acidosis, and certain types of cancer.

A periapical granuloma is a type of dental lesion that occurs at the root tip of a tooth (the apical region) in response to an infection in the pulp tissue. It is a collection of inflammatory cells, mainly composed of lymphocytes, plasma cells, and histiocytes, within the periodontal ligament and alveolar bone. The granuloma forms as a result of the body's attempt to contain the spread of infection from the pulp into the surrounding tissues.

The primary cause of periapical granulomas is untreated dental caries or tooth trauma, which allows bacteria to invade the pulp chamber and eventually reach the apical region. The resulting inflammation can lead to bone resorption and the formation of a radiolucent area around the apex of the affected tooth, visible on a dental radiograph.

Periapical granulomas may not always cause noticeable symptoms, but some patients might experience pain, swelling, or sensitivity in the affected tooth. Treatment typically involves root canal therapy to remove the infected pulp tissue and medicate the canals, followed by a filling or crown to seal and protect the tooth. In some cases, extraction of the tooth may be necessary if the infection is severe or if the tooth cannot be restored.

Maxillary diseases refer to conditions that affect the maxilla, which is the upper bone of the jaw. This bone plays an essential role in functions such as biting, chewing, and speaking, and also forms the upper part of the oral cavity, houses the upper teeth, and supports the nose and the eyes.

Maxillary diseases can be caused by various factors, including infections, trauma, tumors, congenital abnormalities, or systemic conditions. Some common maxillary diseases include:

1. Maxillary sinusitis: Inflammation of the maxillary sinuses, which are air-filled cavities located within the maxilla, can cause symptoms such as nasal congestion, facial pain, and headaches.
2. Periodontal disease: Infection and inflammation of the tissues surrounding the teeth, including the gums and the alveolar bone (which is part of the maxilla), can lead to tooth loss and other complications.
3. Maxillary fractures: Trauma to the face can result in fractures of the maxilla, which can cause pain, swelling, and difficulty breathing or speaking.
4. Maxillary cysts and tumors: Abnormal growths in the maxilla can be benign or malignant and may require surgical intervention.
5. Oral cancer: Cancerous lesions in the oral cavity, including the maxilla, can cause pain, swelling, and difficulty swallowing or speaking.

Treatment for maxillary diseases depends on the specific condition and its severity. Treatment options may include antibiotics, surgery, radiation therapy, or chemotherapy. Regular dental check-ups and good oral hygiene practices can help prevent many maxillary diseases.

In the context of nutrition and health, minerals are inorganic elements that are essential for various bodily functions, such as nerve impulse transmission, muscle contraction, maintaining fluid and electrolyte balance, and bone structure. They are required in small amounts compared to macronutrients (carbohydrates, proteins, and fats) and are obtained from food and water.

Some of the major minerals include calcium, phosphorus, magnesium, sodium, potassium, and chloride, while trace minerals or microminerals are required in even smaller amounts and include iron, zinc, copper, manganese, iodine, selenium, and fluoride.

It's worth noting that the term "minerals" can also refer to geological substances found in the earth, but in medical terminology, it specifically refers to the essential inorganic elements required for human health.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

A "knockout" mouse is a genetically engineered mouse in which one or more genes have been deleted or "knocked out" using molecular biology techniques. This allows researchers to study the function of specific genes and their role in various biological processes, as well as potential associations with human diseases. The mice are generated by introducing targeted DNA modifications into embryonic stem cells, which are then used to create a live animal. Knockout mice have been widely used in biomedical research to investigate gene function, disease mechanisms, and potential therapeutic targets.

A tooth root is the part of a tooth that is embedded in the jawbone and cannot be seen when looking at a person's smile. It is the lower portion of a tooth that typically has a conical shape and anchors the tooth to the jawbone through a periodontal ligament. The tooth root is covered by cementum, a specialized bone-like tissue, and contains nerve endings and blood vessels within its pulp chamber.

The number of roots in a tooth can vary depending on the type of tooth. For example, incisors typically have one root, canines may have one or two roots, premolars usually have one or two roots, and molars often have two to four roots. The primary function of the tooth root is to provide stability and support for the crown of the tooth, allowing it to withstand the forces of biting and chewing.

Procollagen is the precursor protein of collagen, which is a major structural protein in the extracellular matrix of various connective tissues, such as tendons, ligaments, skin, and bones. Procollagen is synthesized inside the cell (in the rough endoplasmic reticulum) and then processed by enzymes to remove specific segments, resulting in the formation of tropocollagen, which are the basic units of collagen fibrils.

Procollagen consists of three polypeptide chains (two alpha-1 and one alpha-2 chain), each containing a central triple-helical domain flanked by non-helical regions at both ends. These non-helical regions, called propeptides, are cleaved off during the processing of procollagen to tropocollagen, allowing the individual collagen molecules to align and form fibrils through covalent cross-linking.

Abnormalities in procollagen synthesis or processing can lead to various connective tissue disorders, such as osteogenesis imperfecta (brittle bone disease) and Ehlers-Danlos syndrome (a group of disorders characterized by joint hypermobility, skin hyperextensibility, and tissue fragility).

Osteosclerosis is a medical term that refers to an abnormal thickening and increased density of bone tissue. This condition can occur as a result of various diseases or conditions, such as certain types of bone cancer, Paget's disease of bone, fluoride poisoning, or chronic infection of the bone. Osteosclerosis can also be seen in some benign conditions, such as osteopetrosis, which is a rare genetic disorder characterized by an excessively hard and dense skeleton.

In some cases, osteosclerosis may not cause any symptoms and may only be discovered on X-rays or other imaging studies. However, in other cases, it can lead to complications such as bone pain, fractures, or deformities. Treatment for osteosclerosis depends on the underlying cause of the condition and may include medications, surgery, or other therapies.

Sialglycoproteins are a type of glycoprotein that have sialic acid as the terminal sugar in their oligosaccharide chains. These complex molecules are abundant on the surface of many cell types and play important roles in various biological processes, including cell recognition, cell-cell interactions, and protection against proteolytic degradation.

The presence of sialic acid on the outermost part of these glycoproteins makes them negatively charged, which can affect their interaction with other molecules such as lectins, antibodies, and enzymes. Sialglycoproteins are also involved in the regulation of various physiological functions, including blood coagulation, inflammation, and immune response.

Abnormalities in sialglycoprotein expression or structure have been implicated in several diseases, such as cancer, autoimmune disorders, and neurodegenerative conditions. Therefore, understanding the biology of sialoglycoproteins is important for developing new diagnostic and therapeutic strategies for these diseases.

The tooth apex is the tip or the narrowed end of the root of a tooth. It is the portion that is located deepest within the jawbone and it contains dental pulp tissue, which includes nerves and blood vessels. The apex plays an essential role in the development and maintenance of a tooth, as well as in the process of root canal treatment, where instruments and materials are introduced through it to clean and fill the root canals. It is also a crucial landmark in endodontic surgery and dental imaging.

In the context of dentistry, a molar is a type of tooth found in the back of the mouth. They are larger and wider than other types of teeth, such as incisors or canines, and have a flat biting surface with multiple cusps. Molars are primarily used for grinding and chewing food into smaller pieces that are easier to swallow. Humans typically have twelve molars in total, including the four wisdom teeth.

In medical terminology outside of dentistry, "molar" can also refer to a unit of mass in the apothecaries' system of measurement, which is equivalent to 4.08 grams. However, this usage is less common and not related to dental or medical anatomy.

Dietary calcium is a type of calcium that is obtained through food sources. Calcium is an essential mineral that is necessary for many bodily functions, including bone formation and maintenance, muscle contraction, nerve impulse transmission, and blood clotting.

The recommended daily intake of dietary calcium varies depending on age, sex, and other factors. For example, the recommended daily intake for adults aged 19-50 is 1000 mg, while women over 50 and men over 70 require 1200 mg per day.

Good dietary sources of calcium include dairy products such as milk, cheese, and yogurt; leafy green vegetables like broccoli and kale; fortified cereals and juices; and certain types of fish, such as salmon and sardines. It is important to note that some foods can inhibit the absorption of calcium, including oxalates found in spinach and rhubarb, and phytates found in whole grains and legumes.

If a person is unable to get enough calcium through their diet, they may need to take calcium supplements. However, it is important to talk to a healthcare provider before starting any new supplement regimen, as excessive intake of calcium can lead to negative health effects.

A dose-response relationship in the context of drugs refers to the changes in the effects or symptoms that occur as the dose of a drug is increased or decreased. Generally, as the dose of a drug is increased, the severity or intensity of its effects also increases. Conversely, as the dose is decreased, the effects of the drug become less severe or may disappear altogether.

The dose-response relationship is an important concept in pharmacology and toxicology because it helps to establish the safe and effective dosage range for a drug. By understanding how changes in the dose of a drug affect its therapeutic and adverse effects, healthcare providers can optimize treatment plans for their patients while minimizing the risk of harm.

The dose-response relationship is typically depicted as a curve that shows the relationship between the dose of a drug and its effect. The shape of the curve may vary depending on the drug and the specific effect being measured. Some drugs may have a steep dose-response curve, meaning that small changes in the dose can result in large differences in the effect. Other drugs may have a more gradual dose-response curve, where larger changes in the dose are needed to produce significant effects.

In addition to helping establish safe and effective dosages, the dose-response relationship is also used to evaluate the potential therapeutic benefits and risks of new drugs during clinical trials. By systematically testing different doses of a drug in controlled studies, researchers can identify the optimal dosage range for the drug and assess its safety and efficacy.

An incisor is a type of tooth that is primarily designed for biting off food pieces rather than chewing or grinding. They are typically chisel-shaped, flat, and have a sharp cutting edge. In humans, there are eight incisors - four on the upper jaw and four on the lower jaw, located at the front of the mouth. Other animals such as dogs, cats, and rodents also have incisors that they use for different purposes like tearing or gnawing.

"Porphyromonas gingivalis" is a gram-negative, anaerobic, rod-shaped bacterium that is commonly found in the oral cavity and is associated with periodontal disease. It is a major pathogen in chronic periodontitis, which is a severe form of gum disease that can lead to destruction of the tissues supporting the teeth, including the gums, periodontal ligament, and alveolar bone.

The bacterium produces several virulence factors, such as proteases and endotoxins, which contribute to its pathogenicity. It has been shown to evade the host's immune response and cause tissue destruction through various mechanisms, including inducing the production of pro-inflammatory cytokines and matrix metalloproteinases.

P. gingivalis has also been linked to several systemic diseases, such as atherosclerosis, rheumatoid arthritis, and Alzheimer's disease, although the exact mechanisms of these associations are not fully understood. Effective oral hygiene practices, including regular brushing, flossing, and professional dental cleanings, can help prevent the overgrowth of P. gingivalis and reduce the risk of periodontal disease.

The periodontal ligament, also known as the "PDL," is the soft tissue that connects the tooth root to the alveolar bone within the dental alveolus (socket). It consists of collagen fibers organized into groups called principal fibers and accessory fibers. These fibers are embedded into both the cementum of the tooth root and the alveolar bone, providing shock absorption during biting and chewing forces, allowing for slight tooth movement, and maintaining the tooth in its position within the socket.

The periodontal ligament plays a crucial role in the health and maintenance of the periodontium, which includes the gingiva (gums), cementum, alveolar bone, and the periodontal ligament itself. Inflammation or infection of the periodontal ligament can lead to periodontal disease, potentially causing tooth loss if not treated promptly and appropriately.

Nuclear factor of activated T-cells (NFAT) transcription factors are a group of proteins that play a crucial role in the regulation of gene transcription in various cells, including immune cells. They are involved in the activation of genes responsible for immune responses, cell survival, differentiation, and development.

NFAT transcription factors can be divided into five main members: NFATC1 (also known as NFAT2 or NFATp), NFATC2 (or NFAT1), NFATC3 (or NFATc), NFATC4 (or NFAT3), and NFAT5 (or TonEBP). These proteins share a highly conserved DNA-binding domain, known as the Rel homology region, which allows them to bind to specific sequences in the promoter or enhancer regions of target genes.

NFATC transcription factors are primarily located in the cytoplasm in their inactive form, bound to inhibitory proteins. Upon stimulation of the cell, typically through calcium-dependent signaling pathways, NFAT proteins get dephosphorylated by calcineurin phosphatase, leading to their nuclear translocation and activation. Once in the nucleus, NFATC transcription factors can form homodimers or heterodimers with other transcription factors, such as AP-1, to regulate gene expression.

In summary, NFATC transcription factors are a family of proteins involved in the regulation of gene transcription, primarily in immune cells, and play critical roles in various cellular processes, including immune responses, differentiation, and development.

Animal disease models are specialized animals, typically rodents such as mice or rats, that have been genetically engineered or exposed to certain conditions to develop symptoms and physiological changes similar to those seen in human diseases. These models are used in medical research to study the pathophysiology of diseases, identify potential therapeutic targets, test drug efficacy and safety, and understand disease mechanisms.

The genetic modifications can include knockout or knock-in mutations, transgenic expression of specific genes, or RNA interference techniques. The animals may also be exposed to environmental factors such as chemicals, radiation, or infectious agents to induce the disease state.

Examples of animal disease models include:

1. Mouse models of cancer: Genetically engineered mice that develop various types of tumors, allowing researchers to study cancer initiation, progression, and metastasis.
2. Alzheimer's disease models: Transgenic mice expressing mutant human genes associated with Alzheimer's disease, which exhibit amyloid plaque formation and cognitive decline.
3. Diabetes models: Obese and diabetic mouse strains like the NOD (non-obese diabetic) or db/db mice, used to study the development of type 1 and type 2 diabetes, respectively.
4. Cardiovascular disease models: Atherosclerosis-prone mice, such as ApoE-deficient or LDLR-deficient mice, that develop plaque buildup in their arteries when fed a high-fat diet.
5. Inflammatory bowel disease models: Mice with genetic mutations affecting intestinal barrier function and immune response, such as IL-10 knockout or SAMP1/YitFc mice, which develop colitis.

Animal disease models are essential tools in preclinical research, but it is important to recognize their limitations. Differences between species can affect the translatability of results from animal studies to human patients. Therefore, researchers must carefully consider the choice of model and interpret findings cautiously when applying them to human diseases.

Calcium radioisotopes are radioactive isotopes of the element calcium. An isotope is a variant of an element that has the same number of protons in its atoms but a different number of neutrons, resulting in different mass numbers. Calcium has several radioisotopes, including calcium-41, calcium-45, calcium-47, and calcium-49.

These radioisotopes are used in various medical applications, such as in diagnostic imaging and research. For example, calcium-45 is commonly used in bone scans to help diagnose conditions like fractures, tumors, or infections. When administered to the patient, the calcium-45 is taken up by the bones, and a special camera can detect the gamma rays emitted by the radioisotope, providing images of the skeleton.

Similarly, calcium-47 is used in research to study calcium metabolism and bone physiology. The short half-life and low energy of the radiation emitted by these radioisotopes make them relatively safe for medical use, with minimal risk of harm to patients. However, as with any medical procedure involving radiation, appropriate precautions must be taken to ensure safety and minimize exposure.

The temporal bone is a paired bone that is located on each side of the skull, forming part of the lateral and inferior walls of the cranial cavity. It is one of the most complex bones in the human body and has several important structures associated with it. The main functions of the temporal bone include protecting the middle and inner ear, providing attachment for various muscles of the head and neck, and forming part of the base of the skull.

The temporal bone is divided into several parts, including the squamous part, the petrous part, the tympanic part, and the styloid process. The squamous part forms the lateral portion of the temporal bone and articulates with the parietal bone. The petrous part is the most medial and superior portion of the temporal bone and contains the inner ear and the semicircular canals. The tympanic part forms the lower and anterior portions of the temporal bone and includes the external auditory meatus or ear canal. The styloid process is a long, slender projection that extends downward from the inferior aspect of the temporal bone and serves as an attachment site for various muscles and ligaments.

The temporal bone plays a crucial role in hearing and balance, as it contains the structures of the middle and inner ear, including the oval window, round window, cochlea, vestibule, and semicircular canals. The stapes bone, one of the three bones in the middle ear, is entirely encased within the petrous portion of the temporal bone. Additionally, the temporal bone contains important structures for facial expression and sensation, including the facial nerve, which exits the skull through the stylomastoid foramen, a small opening in the temporal bone.

Calcitonin receptors (CTRs) are a type of G protein-coupled receptor (GPCR) that bind and respond to the hormone calcitonin. Calcitonin is a peptide hormone secreted by the parafollicular cells (C cells) of the thyroid gland, and plays a crucial role in regulating calcium homeostasis in the body.

CTRs are widely expressed in various tissues and organs, including bone, kidney, intestine, and brain. In bone, CTR activation inhibits osteoclast-mediated bone resorption, thereby increasing bone density and reducing the risk of fractures. In the kidney, CTR activation promotes calcium reabsorption and phosphate excretion, helping to maintain normal serum calcium and phosphate levels.

CTRs are also involved in various physiological processes, such as nociception (pain perception), neuroprotection, and cell proliferation and differentiation. Dysregulation of CTR signaling has been implicated in several diseases, including osteoporosis, hypercalcemia, and cancer.

The medical definition of "Receptors, Calcitonin" refers to the specific proteins that bind calcitonin hormone and mediate its effects on target cells and tissues.

Osteopontin (OPN) is a phosphorylated glycoprotein that is widely distributed in many tissues, including bone, teeth, and mineralized tissues. It plays important roles in various biological processes such as bone remodeling, immune response, wound healing, and tissue repair. In the skeletal system, osteopontin is involved in the regulation of bone formation and resorption by modulating the activity of osteoclasts and osteoblasts. It also plays a role in the development of chronic inflammatory diseases such as rheumatoid arthritis, atherosclerosis, and cancer metastasis to bones. Osteopontin is considered a potential biomarker for various disease states, including bone turnover, cardiovascular disease, and cancer progression.

A tooth socket, also known as an alveolus (plural: alveoli), refers to the hollow cavity or space in the jawbone where a tooth is anchored. The tooth socket is part of the alveolar process, which is the curved part of the maxilla or mandible that contains multiple tooth sockets for the upper and lower teeth, respectively.

Each tooth socket has a specialized tissue called the periodontal ligament, which attaches the root of the tooth to the surrounding bone. This ligament helps absorb forces generated during biting and chewing, allowing for comfortable and efficient mastication while also maintaining the tooth's position within the jawbone. The tooth socket is responsible for providing support, stability, and nourishment to the tooth through its blood vessels and nerves.

The lumbar vertebrae are the five largest and strongest vertebrae in the human spine, located in the lower back region. They are responsible for bearing most of the body's weight and providing stability during movement. The lumbar vertebrae have a characteristic shape, with a large body in the front, which serves as the main weight-bearing structure, and a bony ring in the back, formed by the pedicles, laminae, and processes. This ring encloses and protects the spinal cord and nerves. The lumbar vertebrae are numbered L1 to L5, starting from the uppermost one. They allow for flexion, extension, lateral bending, and rotation movements of the trunk.

Dental cementum is a type of hard connective tissue that covers the root of a tooth. It is primarily composed of calcium salts and collagen fibers, and it serves to attach the periodontal ligaments (the fibers that help secure the tooth in its socket) to the tooth's root. Cementum also helps protect the root of the tooth and contributes to the maintenance of tooth stability. It continues to grow and deposit new layers throughout an individual's life, which can be seen as incremental lines called "cementum annulations."

The spine, also known as the vertebral column, is a complex structure in the human body that is part of the axial skeleton. It is composed of 33 individual vertebrae (except in some people where there are fewer due to fusion of certain vertebrae), intervertebral discs, facet joints, ligaments, muscles, and nerves.

The spine has several important functions:

1. Protection: The spine protects the spinal cord, which is a major component of the nervous system, by enclosing it within a bony canal.
2. Support: The spine supports the head and upper body, allowing us to maintain an upright posture and facilitating movement of the trunk and head.
3. Movement: The spine enables various movements such as flexion (bending forward), extension (bending backward), lateral flexion (bending sideways), and rotation (twisting).
4. Weight-bearing: The spine helps distribute weight and pressure evenly across the body, reducing stress on individual vertebrae and other structures.
5. Blood vessel and nerve protection: The spine protects vital blood vessels and nerves that pass through it, including the aorta, vena cava, and spinal nerves.

The spine is divided into five regions: cervical (7 vertebrae), thoracic (12 vertebrae), lumbar (5 vertebrae), sacrum (5 fused vertebrae), and coccyx (4 fused vertebrae, also known as the tailbone). Each region has unique characteristics that allow for specific functions and adaptations to the body's needs.

The radius is one of the two bones in the forearm in humans and other vertebrates. In humans, it runs from the lateral side of the elbow to the thumb side of the wrist. It is responsible for rotation of the forearm and articulates with the humerus at the elbow and the carpals at the wrist. Any medical condition or injury that affects the radius can impact the movement and function of the forearm and hand.

Tooth exfoliation is not a term that is commonly used in dental or medical literature. However, I believe you may be referring to the natural process of tooth loss that occurs with the shedding of primary (baby) teeth to make way for permanent (adult) teeth. This process is also known as physical or physiological tooth exfoliation.

Exfoliation in this context refers to the separation and shedding of the primary tooth's root from the underlying permanent tooth, allowing the permanent tooth to erupt into its proper position. The primary tooth becomes loose due to the resorption of its roots by the developing permanent tooth beneath it. Eventually, the primary tooth falls out, making room for the adult tooth to emerge and take its place in the dental arch.

It is essential to maintain good oral hygiene during this process to prevent any potential complications such as infection or premature loss of primary teeth.

Organ culture techniques refer to the methods used to maintain or grow intact organs or pieces of organs under controlled conditions in vitro, while preserving their structural and functional characteristics. These techniques are widely used in biomedical research to study organ physiology, pathophysiology, drug development, and toxicity testing.

Organ culture can be performed using a variety of methods, including:

1. Static organ culture: In this method, the organs or tissue pieces are placed on a porous support in a culture dish and maintained in a nutrient-rich medium. The medium is replaced periodically to ensure adequate nutrition and removal of waste products.
2. Perfusion organ culture: This method involves perfusing the organ with nutrient-rich media, allowing for better distribution of nutrients and oxygen throughout the tissue. This technique is particularly useful for studying larger organs such as the liver or kidney.
3. Microfluidic organ culture: In this approach, microfluidic devices are used to create a controlled microenvironment for organ cultures. These devices allow for precise control over the flow of nutrients and waste products, as well as the application of mechanical forces.

Organ culture techniques can be used to study various aspects of organ function, including metabolism, secretion, and response to drugs or toxins. Additionally, these methods can be used to generate three-dimensional tissue models that better recapitulate the structure and function of intact organs compared to traditional two-dimensional cell cultures.

Microradiography is a radiographic technique that uses X-rays to produce detailed images of small specimens, such as microscopic slides or individual cells. In this process, the specimen is placed in close contact with a high-resolution photographic emulsion, and then exposed to X-rays. The resulting image shows the distribution of radiopaque materials within the specimen, providing information about its internal structure and composition at a microscopic level.

Microradiography can be used for various applications in medical research and diagnosis, including the study of bone and tooth microstructure, the analysis of tissue pathology, and the examination of mineralized tissues such as calcifications or osteogenic lesions. The technique offers high resolution and contrast, making it a valuable tool for researchers and clinicians seeking to understand the complex structures and processes that occur at the microscopic level in living organisms.

Teriparatide is a synthetic form of parathyroid hormone (PTH), which is a natural hormone produced by the parathyroid glands in the body. The medication contains the active fragment of PTH, known as 1-34 PTH, and it is used in medical treatment to stimulate new bone formation and increase bone density.

Teriparatide is primarily prescribed for the management of osteoporosis in postmenopausal women and men with a high risk of fractures who have not responded well to other osteoporosis therapies, such as bisphosphonates. It is administered via subcutaneous injection, typically once daily.

By increasing bone formation and reducing bone resorption, teriparatide helps improve bone strength and structure, ultimately decreasing the risk of fractures in treated individuals. The medication's effects on bone metabolism can lead to improvements in bone mineral density (BMD) and microarchitecture, making it an essential tool for managing severe osteoporosis and reducing fracture risk.

Bacteroidaceae is a family of gram-negative, anaerobic bacteria that are commonly found in the human gastrointestinal tract. Infections caused by Bacteroidaceae are relatively rare, but can occur in cases of severe trauma, surgery, or compromised immune systems. These infections may include bacteremia (bacteria in the blood), abscesses, and wound infections. Treatment typically involves the use of antibiotics that are effective against anaerobic bacteria. It is important to note that proper identification of the specific species causing the infection is necessary for appropriate treatment, as different species within Bacteroidaceae may have different susceptibilities to various antibiotics.

Interleukin-1 (IL-1) is a type of cytokine, which are proteins that play a crucial role in cell signaling. Specifically, IL-1 is a pro-inflammatory cytokine that is involved in the regulation of immune and inflammatory responses in the body. It is produced by various cells, including monocytes, macrophages, and dendritic cells, in response to infection or injury.

IL-1 exists in two forms, IL-1α and IL-1β, which have similar biological activities but are encoded by different genes. Both forms of IL-1 bind to the same receptor, IL-1R, and activate intracellular signaling pathways that lead to the production of other cytokines, chemokines, and inflammatory mediators.

IL-1 has a wide range of biological effects, including fever induction, activation of immune cells, regulation of hematopoiesis (the formation of blood cells), and modulation of bone metabolism. Dysregulation of IL-1 production or activity has been implicated in various inflammatory diseases, such as rheumatoid arthritis, gout, and inflammatory bowel disease. Therefore, IL-1 is an important target for the development of therapies aimed at modulating the immune response and reducing inflammation.

Mandibular diseases refer to conditions that affect the mandible, or lower jawbone. These diseases can be classified as congenital (present at birth) or acquired (developing after birth). They can also be categorized based on the tissues involved, such as bone, muscle, or cartilage. Some examples of mandibular diseases include:

1. Mandibular fractures: These are breaks in the lower jawbone that can result from trauma or injury.
2. Osteomyelitis: This is an infection of the bone and surrounding tissues, which can affect the mandible.
3. Temporomandibular joint (TMJ) disorders: These are conditions that affect the joint that connects the jawbone to the skull, causing pain and limited movement.
4. Mandibular tumors: These are abnormal growths that can be benign or malignant, and can develop in any of the tissues of the mandible.
5. Osteonecrosis: This is a condition where the bone tissue dies due to lack of blood supply, which can affect the mandible.
6. Cleft lip and palate: This is a congenital deformity that affects the development of the face and mouth, including the lower jawbone.
7. Mandibular hypoplasia: This is a condition where the lower jawbone does not develop properly, leading to a small or recessed chin.
8. Developmental disorders: These are conditions that affect the growth and development of the mandible, such as condylar hyperplasia or hemifacial microsomia.

Glycoproteins are complex proteins that contain oligosaccharide chains (glycans) covalently attached to their polypeptide backbone. These glycans are linked to the protein through asparagine residues (N-linked) or serine/threonine residues (O-linked). Glycoproteins play crucial roles in various biological processes, including cell recognition, cell-cell interactions, cell adhesion, and signal transduction. They are widely distributed in nature and can be found on the outer surface of cell membranes, in extracellular fluids, and as components of the extracellular matrix. The structure and composition of glycoproteins can vary significantly depending on their function and location within an organism.

Amino acids are organic compounds that serve as the building blocks of proteins. They consist of a central carbon atom, also known as the alpha carbon, which is bonded to an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom (H), and a variable side chain (R group). The R group can be composed of various combinations of atoms such as hydrogen, oxygen, sulfur, nitrogen, and carbon, which determine the unique properties of each amino acid.

There are 20 standard amino acids that are encoded by the genetic code and incorporated into proteins during translation. These include:

1. Alanine (Ala)
2. Arginine (Arg)
3. Asparagine (Asn)
4. Aspartic acid (Asp)
5. Cysteine (Cys)
6. Glutamine (Gln)
7. Glutamic acid (Glu)
8. Glycine (Gly)
9. Histidine (His)
10. Isoleucine (Ile)
11. Leucine (Leu)
12. Lysine (Lys)
13. Methionine (Met)
14. Phenylalanine (Phe)
15. Proline (Pro)
16. Serine (Ser)
17. Threonine (Thr)
18. Tryptophan (Trp)
19. Tyrosine (Tyr)
20. Valine (Val)

Additionally, there are several non-standard or modified amino acids that can be incorporated into proteins through post-translational modifications, such as hydroxylation, methylation, and phosphorylation. These modifications expand the functional diversity of proteins and play crucial roles in various cellular processes.

Amino acids are essential for numerous biological functions, including protein synthesis, enzyme catalysis, neurotransmitter production, energy metabolism, and immune response regulation. Some amino acids can be synthesized by the human body (non-essential), while others must be obtained through dietary sources (essential).

Coculture techniques refer to a type of experimental setup in which two or more different types of cells or organisms are grown and studied together in a shared culture medium. This method allows researchers to examine the interactions between different cell types or species under controlled conditions, and to study how these interactions may influence various biological processes such as growth, gene expression, metabolism, and signal transduction.

Coculture techniques can be used to investigate a wide range of biological phenomena, including the effects of host-microbe interactions on human health and disease, the impact of different cell types on tissue development and homeostasis, and the role of microbial communities in shaping ecosystems. These techniques can also be used to test the efficacy and safety of new drugs or therapies by examining their effects on cells grown in coculture with other relevant cell types.

There are several different ways to establish cocultures, depending on the specific research question and experimental goals. Some common methods include:

1. Mixed cultures: In this approach, two or more cell types are simply mixed together in a culture dish or flask and allowed to grow and interact freely.
2. Cell-layer cultures: Here, one cell type is grown on a porous membrane or other support structure, while the second cell type is grown on top of it, forming a layered coculture.
3. Conditioned media cultures: In this case, one cell type is grown to confluence and its culture medium is collected and then used to grow a second cell type. This allows the second cell type to be exposed to any factors secreted by the first cell type into the medium.
4. Microfluidic cocultures: These involve growing cells in microfabricated channels or chambers, which allow for precise control over the spatial arrangement and flow of nutrients, waste products, and signaling molecules between different cell types.

Overall, coculture techniques provide a powerful tool for studying complex biological systems and gaining insights into the mechanisms that underlie various physiological and pathological processes.

Multiple myeloma is a type of cancer that forms in a type of white blood cell called a plasma cell. Plasma cells help your body fight infection by producing antibodies. In multiple myeloma, cancerous plasma cells accumulate in the bone marrow and crowd out healthy blood cells. Rather than producing useful antibodies, the cancer cells produce abnormal proteins that can cause complications such as kidney damage, bone pain and fractures.

Multiple myeloma is a type of cancer called a plasma cell neoplasm. Plasma cell neoplasms are diseases in which there is an overproduction of a single clone of plasma cells. In multiple myeloma, this results in the crowding out of normal plasma cells, red and white blood cells and platelets, leading to many of the complications associated with the disease.

The abnormal proteins produced by the cancer cells can also cause damage to organs and tissues in the body. These abnormal proteins can be detected in the blood or urine and are often used to monitor the progression of multiple myeloma.

Multiple myeloma is a relatively uncommon cancer, but it is the second most common blood cancer after non-Hodgkin lymphoma. It typically occurs in people over the age of 65, and men are more likely to develop multiple myeloma than women. While there is no cure for multiple myeloma, treatments such as chemotherapy, radiation therapy, and stem cell transplantation can help manage the disease and its symptoms, and improve quality of life.

Integrin-binding sialoprotein (IBSP) is a non-collagenous protein found in bones and teeth. It is also known as bone sialoprotein II or acidic glycoprotein 34. IBSP plays a role in the regulation of biomineralization, which is the process by which minerals are deposited in biological tissues.

IBSP contains several functional domains that allow it to interact with other proteins and molecules. One such domain is an arginine-glycine-aspartic acid (RGD) motif, which can bind to integrin receptors on the surface of cells. This interaction helps regulate the attachment and behavior of cells in bone tissue.

IBSP also contains a large number of sialic acid residues, which give it its name and contribute to its negative charge. These residues may play a role in protecting the protein from degradation and helping it interact with other molecules in the extracellular matrix.

Overall, IBSP is an important component of bone tissue and plays a key role in regulating the formation and maintenance of bones and teeth.

Dentin is the hard, calcified tissue that lies beneath the enamel and cementum of a tooth. It forms the majority of the tooth's structure and is composed primarily of mineral salts (hydroxyapatite), collagenous proteins, and water. Dentin has a tubular structure, with microscopic channels called dentinal tubules that radiate outward from the pulp chamber (the center of the tooth containing nerves and blood vessels) to the exterior of the tooth. These tubules contain fluid and nerve endings that are responsible for the tooth's sensitivity to various stimuli such as temperature changes, pressure, or decay. Dentin plays a crucial role in protecting the dental pulp while also providing support and structure to the overlying enamel and cementum.

Carrier proteins, also known as transport proteins, are a type of protein that facilitates the movement of molecules across cell membranes. They are responsible for the selective and active transport of ions, sugars, amino acids, and other molecules from one side of the membrane to the other, against their concentration gradient. This process requires energy, usually in the form of ATP (adenosine triphosphate).

Carrier proteins have a specific binding site for the molecule they transport, and undergo conformational changes upon binding, which allows them to move the molecule across the membrane. Once the molecule has been transported, the carrier protein returns to its original conformation, ready to bind and transport another molecule.

Carrier proteins play a crucial role in maintaining the balance of ions and other molecules inside and outside of cells, and are essential for many physiological processes, including nerve impulse transmission, muscle contraction, and nutrient uptake.

Sprague-Dawley rats are a strain of albino laboratory rats that are widely used in scientific research. They were first developed by researchers H.H. Sprague and R.C. Dawley in the early 20th century, and have since become one of the most commonly used rat strains in biomedical research due to their relatively large size, ease of handling, and consistent genetic background.

Sprague-Dawley rats are outbred, which means that they are genetically diverse and do not suffer from the same limitations as inbred strains, which can have reduced fertility and increased susceptibility to certain diseases. They are also characterized by their docile nature and low levels of aggression, making them easier to handle and study than some other rat strains.

These rats are used in a wide variety of research areas, including toxicology, pharmacology, nutrition, cancer, and behavioral studies. Because they are genetically diverse, Sprague-Dawley rats can be used to model a range of human diseases and conditions, making them an important tool in the development of new drugs and therapies.

The periodontium is a complex structure in the oral cavity that surrounds and supports the teeth. It consists of four main components:
1. Gingiva (gums): The pink, soft tissue that covers the crown of the tooth and extends down to the neck of the tooth, where it meets the cementum.
2. Cementum: A specialized, calcified tissue that covers the root of the tooth and provides a surface for the periodontal ligament fibers to attach.
3. Periodontal ligament (PDL): A highly vascular and cell-rich connective tissue that attaches the cementum of the tooth root to the alveolar bone, allowing for tooth mobility and absorption of forces during chewing.
4. Alveolar bone: The portion of the jawbone that contains the sockets (alveoli) for the teeth. It is a spongy bone with a rich blood supply that responds to mechanical stresses from biting and chewing, undergoing remodeling throughout life.

Periodontal diseases, such as gingivitis and periodontitis, affect the health and integrity of the periodontium, leading to inflammation, bleeding, pocket formation, bone loss, and ultimately tooth loss if left untreated.

Cytoplasmic receptors and nuclear receptors are two types of intracellular receptors that play crucial roles in signal transduction pathways and regulation of gene expression. They are classified based on their location within the cell. Here are the medical definitions for each:

1. Cytoplasmic Receptors: These are a group of intracellular receptors primarily found in the cytoplasm of cells, which bind to specific hormones, growth factors, or other signaling molecules. Upon binding, these receptors undergo conformational changes that allow them to interact with various partners, such as adapter proteins and enzymes, leading to activation of downstream signaling cascades. These pathways ultimately result in modulation of cellular processes like proliferation, differentiation, and apoptosis. Examples of cytoplasmic receptors include receptor tyrosine kinases (RTKs), serine/threonine kinase receptors, and cytokine receptors.
2. Nuclear Receptors: These are a distinct class of intracellular receptors that reside primarily in the nucleus of cells. They bind to specific ligands, such as steroid hormones, thyroid hormones, vitamin D, retinoic acid, and various other lipophilic molecules. Upon binding, nuclear receptors undergo conformational changes that facilitate their interaction with co-regulatory proteins and the DNA. This interaction results in the modulation of gene transcription, ultimately leading to alterations in protein expression and cellular responses. Examples of nuclear receptors include estrogen receptor (ER), androgen receptor (AR), glucocorticoid receptor (GR), thyroid hormone receptor (TR), vitamin D receptor (VDR), and peroxisome proliferator-activated receptors (PPARs).

Both cytoplasmic and nuclear receptors are essential components of cellular communication networks, allowing cells to respond appropriately to extracellular signals and maintain homeostasis. Dysregulation of these receptors has been implicated in various diseases, including cancer, diabetes, and autoimmune disorders.

The ulna is one of the two long bones in the forearm, the other being the radius. It runs from the elbow to the wrist and is located on the medial side of the forearm, next to the bone called the humerus in the upper arm. The ulna plays a crucial role in the movement of the forearm and also serves as an attachment site for various muscles.

'Foot bones,' also known as the tarsal and metatarsal bones, are the 26 bones that make up the foot in humans. The foot is divided into three parts: the hindfoot, midfoot, and forefoot.

The hindfoot contains two bones: the talus, which connects to the leg bone (tibia), and the calcaneus (heel bone). These bones form the ankle joint and heel.

The midfoot is made up of five irregularly shaped bones called the navicular, cuboid, and three cuneiform bones. These bones help form the arch of the foot and connect the hindfoot to the forefoot.

The forefoot contains the metatarsals (five long bones) and the phalanges (14 small bones). The metatarsals connect the midfoot to the toes, while the phalanges make up the toes themselves.

These bones work together to provide stability, support, and movement for the foot, allowing us to walk, run, and jump.

Scanning electron microscopy (SEM) is a type of electron microscopy that uses a focused beam of electrons to scan the surface of a sample and produce a high-resolution image. In SEM, a beam of electrons is scanned across the surface of a specimen, and secondary electrons are emitted from the sample due to interactions between the electrons and the atoms in the sample. These secondary electrons are then detected by a detector and used to create an image of the sample's surface topography. SEM can provide detailed images of the surface of a wide range of materials, including metals, polymers, ceramics, and biological samples. It is commonly used in materials science, biology, and electronics for the examination and analysis of surfaces at the micro- and nanoscale.

Membrane glycoproteins are proteins that contain oligosaccharide chains (glycans) covalently attached to their polypeptide backbone. They are integral components of biological membranes, spanning the lipid bilayer and playing crucial roles in various cellular processes.

The glycosylation of these proteins occurs in the endoplasmic reticulum (ER) and Golgi apparatus during protein folding and trafficking. The attached glycans can vary in structure, length, and composition, which contributes to the diversity of membrane glycoproteins.

Membrane glycoproteins can be classified into two main types based on their orientation within the lipid bilayer:

1. Type I (N-linked): These glycoproteins have a single transmembrane domain and an extracellular N-terminus, where the oligosaccharides are predominantly attached via asparagine residues (Asn-X-Ser/Thr sequon).
2. Type II (C-linked): These glycoproteins possess two transmembrane domains and an intracellular C-terminus, with the oligosaccharides linked to tryptophan residues via a mannose moiety.

Membrane glycoproteins are involved in various cellular functions, such as:

* Cell adhesion and recognition
* Receptor-mediated signal transduction
* Enzymatic catalysis
* Transport of molecules across membranes
* Cell-cell communication
* Immunological responses

Some examples of membrane glycoproteins include cell surface receptors (e.g., growth factor receptors, cytokine receptors), adhesion molecules (e.g., integrins, cadherins), and transporters (e.g., ion channels, ABC transporters).

Hydroxycholecalciferols are metabolites of vitamin D that are formed in the liver and kidneys. They are important for maintaining calcium homeostasis in the body by promoting the absorption of calcium from the gut and reabsorption of calcium from the kidneys.

The two main forms of hydroxycholecalciferols are 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH)2D). 25-hydroxyvitamin D is the major circulating form of vitamin D in the body and is used as a clinical measure of vitamin D status. It is converted to 1,25-dihydroxyvitamin D in the kidneys by the enzyme 1α-hydroxylase, which is activated in response to low serum calcium or high phosphate levels.

1,25-dihydroxyvitamin D is the biologically active form of vitamin D and plays a critical role in regulating calcium homeostasis by increasing intestinal calcium absorption and promoting bone health. Deficiency in hydroxycholecalciferols can lead to rickets in children and osteomalacia or osteoporosis in adults, characterized by weakened bones and increased risk of fractures.

Polymethyl methacrylate (PMMA) is a type of synthetic resin that is widely used in the medical field due to its biocompatibility and versatility. It is a transparent, rigid, and lightweight material that can be easily molded into different shapes and forms. Here are some of the medical definitions of PMMA:

1. A biocompatible acrylic resin used in various medical applications such as bone cement, intraocular lenses, dental restorations, and drug delivery systems.
2. A type of synthetic material that is used as a bone cement to fix prosthetic joint replacements and vertebroplasty for the treatment of spinal fractures.
3. A transparent and shatter-resistant material used in the manufacture of medical devices such as intravenous (IV) fluid bags, dialyzer housings, and oxygenators.
4. A drug delivery system that can be used to administer drugs locally or systemically, such as intraocular sustained-release drug implants for the treatment of chronic eye diseases.
5. A component of dental restorations such as fillings, crowns, and bridges due to its excellent mechanical properties and esthetic qualities.

Overall, PMMA is a versatile and valuable material in the medical field, with numerous applications that take advantage of its unique properties.

A bicuspid valve, also known as a mitral valve in the heart, is a heart valve that has two leaflets or cusps. It lies between the left atrium and the left ventricle and helps to regulate blood flow between these two chambers of the heart. In a healthy heart, the bicuspid valve opens to allow blood to flow from the left atrium into the left ventricle and closes tightly to prevent blood from flowing back into the left atrium during contraction of the ventricle.

A congenital heart defect known as a bicuspid aortic valve occurs when the aortic valve, which normally has three leaflets or cusps, only has two. This can lead to narrowing of the valve (aortic stenosis) or leakage of the valve (aortic regurgitation), which can cause symptoms and may require medical treatment.

The humerus is the long bone in the upper arm that extends from the shoulder joint (glenohumeral joint) to the elbow joint. It articulates with the glenoid cavity of the scapula to form the shoulder joint and with the radius and ulna bones at the elbow joint. The proximal end of the humerus has a rounded head that provides for movement in multiple planes, making it one of the most mobile joints in the body. The greater and lesser tubercles are bony prominences on the humeral head that serve as attachment sites for muscles that move the shoulder and arm. The narrow shaft of the humerus provides stability and strength for weight-bearing activities, while the distal end forms two articulations: one with the ulna (trochlea) and one with the radius (capitulum). Together, these structures allow for a wide range of motion in the shoulder and elbow joints.

The "femur neck" is the narrow, upper part of the femur (thigh bone) where it connects to the pelvis. It is the region through which the femoral head articulates with the acetabulum to form the hip joint. The femur neck is a common site for fractures, especially in older adults with osteoporosis.

I believe there may be some confusion in your question as Polyethylenes are not a medical term, but rather a category of synthetic polymers commonly used in various industrial and medical applications. Here's a brief overview:

Polyethylene (PE) is a type of thermoplastic polymer made from the monomer ethylene. It is a versatile material with numerous applications due to its chemical resistance, durability, and flexibility. There are several types of polyethylenes, including:

1. Low-density polyethylene (LDPE): This type has a lower density and more branching in its molecular structure, which results in less crystallinity. LDPE is known for its flexibility and is often used in packaging films, bags, and containers.
2. High-density polyethylene (HDPE): HDPE has a higher density and less branching, resulting in greater crystallinity. It is more rigid than LDPE and is commonly used in applications such as bottles, pipes, and containers.
3. Linear low-density polyethylene (LLDPE): This type combines the flexibility of LDPE with some of the strength and rigidity of HDPE. LLDPE has fewer branches than LDPE but more than HDPE. It is often used in film applications, such as stretch wrap and agricultural films.
4. Ultra-high molecular weight polyethylene (UHMWPE): UHMWPE has an extremely high molecular weight, resulting in exceptional wear resistance, impact strength, and chemical resistance. It is commonly used in medical applications, such as orthopedic implants and joint replacements, due to its biocompatibility and low friction coefficient.

While polyethylenes are not a medical term per se, they do have significant medical applications, particularly UHMWPE in orthopedic devices.

ICR (Institute of Cancer Research) is a strain of albino Swiss mice that are widely used in scientific research. They are an outbred strain, which means that they have been bred to maintain maximum genetic heterogeneity. However, it is also possible to find inbred strains of ICR mice, which are genetically identical individuals produced by many generations of brother-sister mating.

Inbred ICR mice are a specific type of ICR mouse that has been inbred for at least 20 generations. This means that they have a high degree of genetic uniformity and are essentially genetically identical to one another. Inbred strains of mice are often used in research because their genetic consistency makes them more reliable models for studying biological phenomena and testing new therapies or treatments.

It is important to note that while inbred ICR mice may be useful for certain types of research, they do not necessarily represent the genetic diversity found in human populations. Therefore, it is important to consider the limitations of using any animal model when interpreting research findings and applying them to human health.

Gingiva is the medical term for the soft tissue that surrounds the teeth and forms the margin of the dental groove, also known as the gum. It extends from the mucogingival junction to the base of the cervical third of the tooth root. The gingiva plays a crucial role in protecting and supporting the teeth and maintaining oral health by providing a barrier against microbial invasion and mechanical injury.

Periapical periodontitis is a medical condition that affects the tissues surrounding the root tip (apex) of a tooth. It is typically caused by bacterial infection that originates from the dental pulp, which is the soft tissue inside the tooth that contains nerves and blood vessels. When the dental pulp becomes inflamed or infected due to decay or injury, it can lead to periapical periodontitis if left untreated.

The infection spreads from the pulp through the root canal and forms an abscess at the tip of the tooth root. This results in inflammation and destruction of the surrounding bone and periodontal tissues, leading to symptoms such as pain, swelling, tenderness, and sensitivity to hot or cold temperatures.

Periapical periodontitis is usually treated with root canal therapy, which involves removing the infected pulp tissue, cleaning and disinfecting the root canal, and filling and sealing the space to prevent reinfection. In some cases, antibiotics may also be prescribed to help clear up any residual infection. If left untreated, periapical periodontitis can lead to more serious complications such as tooth loss or spread of infection to other parts of the body.

Renal osteodystrophy is a bone disease that occurs in individuals with chronic kidney disease (CKD). It is characterized by abnormalities in the bones' structure and mineral composition due to disturbances in the metabolism of calcium, phosphorus, and vitamin D. These metabolic disturbances result from the kidneys' decreased ability to maintain balance in the levels of these minerals and hormones.

Renal osteodystrophy can manifest as several bone disorders, including:

1. Osteitis fibrosa cystica: Increased bone turnover due to excessive parathyroid hormone (PTH) production, leading to high levels of alkaline phosphatase and increased resorption of bones.
2. Adynamic bone disease: Decreased bone turnover due to reduced PTH levels, resulting in low bone formation rates and increased fracture risk.
3. Mixed uremic osteodystrophy: A combination of high and low bone turnover, with varying degrees of mineralization defects.
4. Osteomalacia: Defective mineralization of bones due to vitamin D deficiency or resistance, leading to soft and weak bones.

Symptoms of renal osteodystrophy may include bone pain, muscle weakness, fractures, deformities, and growth retardation in children. Diagnosis typically involves laboratory tests, imaging studies, and sometimes bone biopsies. Treatment focuses on correcting the metabolic imbalances through dietary modifications, medications (such as phosphate binders, vitamin D analogs, and calcimimetics), and addressing any secondary hyperparathyroidism if present.

A bone cyst is a fluid-filled sac that develops within a bone. It can be classified as either simple (unicameral) or aneurysmal. Simple bone cysts are more common in children and adolescents, and they typically affect the long bones of the arms or legs. These cysts are usually asymptomatic unless they become large enough to weaken the bone and cause a fracture. Aneurysmal bone cysts, on the other hand, can occur at any age and can affect any bone, but they are most common in the leg bones and spine. They are characterized by rapidly growing blood-filled sacs that can cause pain, swelling, and fractures.

Both types of bone cysts may be treated with observation, medication, or surgery depending on their size, location, and symptoms. It is important to note that while these cysts can be benign, they should still be evaluated and monitored by a healthcare professional to ensure proper treatment and prevention of complications.

Biomechanics is the application of mechanical laws to living structures and systems, particularly in the field of medicine and healthcare. A biomechanical phenomenon refers to a observable event or occurrence that involves the interaction of biological tissues or systems with mechanical forces. These phenomena can be studied at various levels, from the molecular and cellular level to the tissue, organ, and whole-body level.

Examples of biomechanical phenomena include:

1. The way that bones and muscles work together to produce movement (known as joint kinematics).
2. The mechanical behavior of biological tissues such as bone, cartilage, tendons, and ligaments under various loads and stresses.
3. The response of cells and tissues to mechanical stimuli, such as the way that bone tissue adapts to changes in loading conditions (known as Wolff's law).
4. The biomechanics of injury and disease processes, such as the mechanisms of joint injury or the development of osteoarthritis.
5. The use of mechanical devices and interventions to treat medical conditions, such as orthopedic implants or assistive devices for mobility impairments.

Understanding biomechanical phenomena is essential for developing effective treatments and prevention strategies for a wide range of medical conditions, from musculoskeletal injuries to neurological disorders.

Messenger RNA (mRNA) is a type of RNA (ribonucleic acid) that carries genetic information copied from DNA in the form of a series of three-base code "words," each of which specifies a particular amino acid. This information is used by the cell's machinery to construct proteins, a process known as translation. After being transcribed from DNA, mRNA travels out of the nucleus to the ribosomes in the cytoplasm where protein synthesis occurs. Once the protein has been synthesized, the mRNA may be degraded and recycled. Post-transcriptional modifications can also occur to mRNA, such as alternative splicing and addition of a 5' cap and a poly(A) tail, which can affect its stability, localization, and translation efficiency.

The parathyroid glands are four small endocrine glands located in the neck, usually near or behind the thyroid gland. They secrete parathyroid hormone (PTH), which plays a critical role in regulating calcium and phosphate levels in the blood and bones. PTH helps maintain the balance of these minerals by increasing the absorption of calcium from food in the intestines, promoting reabsorption of calcium in the kidneys, and stimulating the release of calcium from bones when needed. Additionally, PTH decreases the excretion of calcium through urine and reduces phosphate reabsorption in the kidneys, leading to increased phosphate excretion. Disorders of the parathyroid glands can result in conditions such as hyperparathyroidism (overactive glands) or hypoparathyroidism (underactive glands), which can have significant impacts on calcium and phosphate homeostasis and overall health.

Imidazoles are a class of heterocyclic organic compounds that contain a double-bonded nitrogen atom and two additional nitrogen atoms in the ring. They have the chemical formula C3H4N2. In a medical context, imidazoles are commonly used as antifungal agents. Some examples of imidazole-derived antifungals include clotrimazole, miconazole, and ketoconazole. These medications work by inhibiting the synthesis of ergosterol, a key component of fungal cell membranes, leading to increased permeability and death of the fungal cells. Imidazoles may also have anti-inflammatory, antibacterial, and anticancer properties.

A Giant Cell Tumor (GCT) of bone is a relatively uncommon, locally aggressive tumor that can sometimes become malignant. It is characterized by the presence of multinucleated giant cells which are distributed throughout the tumor tissue. These giant cells are thought to be derived from osteoclasts, which are specialized cells responsible for bone resorption.

GCTs typically affect adults in their 20s and 30s, with a slight female predominance. The most common sites of involvement include the long bones near the knee (distal femur and proximal tibia), as well as the distal radius, sacrum, and spine.

The tumor usually presents as pain and swelling in the affected area, sometimes accompanied by restricted mobility or pathological fractures due to bone weakening. The diagnosis is typically made based on imaging studies (such as X-rays, CT scans, or MRI) and confirmed through a biopsy.

Treatment options for GCTs of bone may include intralesional curettage with or without the use of adjuvant therapies (like phenol, liquid nitrogen, or cement), radiation therapy, or surgical resection. In some cases, systemic treatments like denosumab, a monoclonal antibody targeting RANKL, may be used to control the growth and spread of the tumor. Regular follow-ups are essential to monitor for potential recurrence, which can occur in up to 50% of cases within five years after treatment.

Postmenopause is a stage in a woman's life that follows 12 months after her last menstrual period (menopause) has occurred. During this stage, the ovaries no longer release eggs and produce lower levels of estrogen and progesterone hormones. The reduced levels of these hormones can lead to various physical changes and symptoms, such as hot flashes, vaginal dryness, and mood changes. Postmenopause is also associated with an increased risk of certain health conditions, including osteoporosis and heart disease. It's important for women in postmenopause to maintain a healthy lifestyle, including regular exercise, a balanced diet, and routine medical check-ups to monitor their overall health and manage any potential risks.

Cartilage is a type of connective tissue that is found throughout the body in various forms. It is made up of specialized cells called chondrocytes, which are embedded in a firm, flexible matrix composed of collagen fibers and proteoglycans. This unique structure gives cartilage its characteristic properties of being both strong and flexible.

There are three main types of cartilage in the human body: hyaline cartilage, elastic cartilage, and fibrocartilage.

1. Hyaline cartilage is the most common type and is found in areas such as the articular surfaces of bones (where they meet to form joints), the nose, trachea, and larynx. It has a smooth, glassy appearance and provides a smooth, lubricated surface for joint movement.
2. Elastic cartilage contains more elastin fibers than hyaline cartilage, which gives it greater flexibility and resilience. It is found in structures such as the external ear and parts of the larynx and epiglottis.
3. Fibrocartilage has a higher proportion of collagen fibers and fewer chondrocytes than hyaline or elastic cartilage. It is found in areas that require high tensile strength, such as the intervertebral discs, menisci (found in joints like the knee), and the pubic symphysis.

Cartilage plays a crucial role in supporting and protecting various structures within the body, allowing for smooth movement and providing a cushion between bones to absorb shock and prevent wear and tear. However, cartilage has limited capacity for self-repair and regeneration, making damage or degeneration of cartilage tissue a significant concern in conditions such as osteoarthritis.

Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) is a laboratory technique used in molecular biology to amplify and detect specific DNA sequences. This technique is particularly useful for the detection and quantification of RNA viruses, as well as for the analysis of gene expression.

The process involves two main steps: reverse transcription and polymerase chain reaction (PCR). In the first step, reverse transcriptase enzyme is used to convert RNA into complementary DNA (cDNA) by reading the template provided by the RNA molecule. This cDNA then serves as a template for the PCR amplification step.

In the second step, the PCR reaction uses two primers that flank the target DNA sequence and a thermostable polymerase enzyme to repeatedly copy the targeted cDNA sequence. The reaction mixture is heated and cooled in cycles, allowing the primers to anneal to the template, and the polymerase to extend the new strand. This results in exponential amplification of the target DNA sequence, making it possible to detect even small amounts of RNA or cDNA.

RT-PCR is a sensitive and specific technique that has many applications in medical research and diagnostics, including the detection of viruses such as HIV, hepatitis C virus, and SARS-CoV-2 (the virus that causes COVID-19). It can also be used to study gene expression, identify genetic mutations, and diagnose genetic disorders.

Prosthesis failure is a term used to describe a situation where a prosthetic device, such as an artificial joint or limb, has stopped functioning or failed to meet its intended purpose. This can be due to various reasons, including mechanical failure, infection, loosening of the device, or a reaction to the materials used in the prosthesis.

Mechanical failure can occur due to wear and tear, manufacturing defects, or improper use of the prosthetic device. Infection can also lead to prosthesis failure, particularly in cases where the prosthesis is implanted inside the body. The immune system may react to the presence of the foreign material, leading to inflammation and infection.

Loosening of the prosthesis can also cause it to fail over time, as the device becomes less stable and eventually stops working properly. Additionally, some people may have a reaction to the materials used in the prosthesis, leading to tissue damage or other complications that can result in prosthesis failure.

In general, prosthesis failure can lead to decreased mobility, pain, and the need for additional surgeries or treatments to correct the problem. It is important for individuals with prosthetic devices to follow their healthcare provider's instructions carefully to minimize the risk of prosthesis failure and ensure that the device continues to function properly over time.

Signal transduction is the process by which a cell converts an extracellular signal, such as a hormone or neurotransmitter, into an intracellular response. This involves a series of molecular events that transmit the signal from the cell surface to the interior of the cell, ultimately resulting in changes in gene expression, protein activity, or metabolism.

The process typically begins with the binding of the extracellular signal to a receptor located on the cell membrane. This binding event activates the receptor, which then triggers a cascade of intracellular signaling molecules, such as second messengers, protein kinases, and ion channels. These molecules amplify and propagate the signal, ultimately leading to the activation or inhibition of specific cellular responses.

Signal transduction pathways are highly regulated and can be modulated by various factors, including other signaling molecules, post-translational modifications, and feedback mechanisms. Dysregulation of these pathways has been implicated in a variety of diseases, including cancer, diabetes, and neurological disorders.

Dinoprostone is a prostaglandin E2 analog used in medical practice for the induction of labor and ripening of the cervix in pregnant women. It is available in various forms, including vaginal suppositories, gel, and tablets. Dinoprostone works by stimulating the contraction of uterine muscles and promoting cervical dilation, which helps in facilitating a successful delivery.

It's important to note that dinoprostone should only be administered under the supervision of a healthcare professional, as its use is associated with certain risks and side effects, including uterine hyperstimulation, fetal distress, and maternal infection. The dosage and duration of treatment are carefully monitored to minimize these risks and ensure the safety of both the mother and the baby.

Vitamin D is a fat-soluble secosteroid that is crucial for the regulation of calcium and phosphate levels in the body, which are essential for maintaining healthy bones and teeth. It can be synthesized by the human body when skin is exposed to ultraviolet-B (UVB) rays from sunlight, or it can be obtained through dietary sources such as fatty fish, fortified dairy products, and supplements. There are two major forms of vitamin D: vitamin D2 (ergocalciferol), which is found in some plants and fungi, and vitamin D3 (cholecalciferol), which is produced in the skin or obtained from animal-derived foods. Both forms need to undergo two hydroxylations in the body to become biologically active as calcitriol (1,25-dihydroxyvitamin D3), the hormonally active form of vitamin D. This activated form exerts its effects by binding to the vitamin D receptor (VDR) found in various tissues, including the small intestine, bone, kidney, and immune cells, thereby influencing numerous physiological processes such as calcium homeostasis, bone metabolism, cell growth, and immune function.

Macrophages are a type of white blood cell that are an essential part of the immune system. They are large, specialized cells that engulf and destroy foreign substances, such as bacteria, viruses, parasites, and fungi, as well as damaged or dead cells. Macrophages are found throughout the body, including in the bloodstream, lymph nodes, spleen, liver, lungs, and connective tissues. They play a critical role in inflammation, immune response, and tissue repair and remodeling.

Macrophages originate from monocytes, which are a type of white blood cell produced in the bone marrow. When monocytes enter the tissues, they differentiate into macrophages, which have a larger size and more specialized functions than monocytes. Macrophages can change their shape and move through tissues to reach sites of infection or injury. They also produce cytokines, chemokines, and other signaling molecules that help coordinate the immune response and recruit other immune cells to the site of infection or injury.

Macrophages have a variety of surface receptors that allow them to recognize and respond to different types of foreign substances and signals from other cells. They can engulf and digest foreign particles, bacteria, and viruses through a process called phagocytosis. Macrophages also play a role in presenting antigens to T cells, which are another type of immune cell that helps coordinate the immune response.

Overall, macrophages are crucial for maintaining tissue homeostasis, defending against infection, and promoting wound healing and tissue repair. Dysregulation of macrophage function has been implicated in a variety of diseases, including cancer, autoimmune disorders, and chronic inflammatory conditions.

Methyl Methacrylates (MMA) are a family of synthetic materials that are commonly used in the medical field, particularly in orthopedic and dental applications. Medically, MMA is often used as a bone cement to fix prosthetic implants, such as artificial hips or knees, into place during surgeries.

Methyl methacrylates consist of a type of acrylic resin that hardens when mixed with a liquid catalyst. This property allows it to be easily molded and shaped before it sets, making it ideal for use in surgical procedures where precise positioning is required. Once hardened, MMA forms a strong, stable bond with the bone, helping to secure the implant in place.

It's important to note that while MMA is widely used in medical applications, there have been concerns about its safety in certain situations. For example, some studies have suggested that high levels of methyl methacrylate fumes released during the setting process may be harmful to both patients and surgical staff. Therefore, appropriate precautions should be taken when using MMA-based products in medical settings.

Panoramic radiography is a specialized type of dental X-ray imaging that captures a panoramic view of the entire mouth, including the teeth, upper and lower jaws, and surrounding structures. It uses a special machine that rotates around the head, capturing images as it moves. This technique provides a two-dimensional image that is helpful in diagnosing and planning treatment for various dental conditions such as impacted teeth, bone abnormalities, and jaw disorders.

The panoramic radiograph can also be used to assess the development and positioning of wisdom teeth, detect cysts or tumors in the jaws, and evaluate the effects of trauma or injury to the mouth. It is a valuable tool for dental professionals as it allows them to see a comprehensive view of the oral structures, which may not be visible with traditional X-ray techniques.

It's important to note that while panoramic radiography provides valuable information, it should be used in conjunction with other diagnostic tools and clinical examinations to ensure accurate diagnosis and treatment planning.

The dental sac, also known as the dental follicle, is a soft tissue structure that surrounds the developing tooth crown during odontogenesis, which is the process of tooth development. It is derived from the ectoderm and mesenchyme of the embryonic oral cavity. The dental sac gives rise to several important structures associated with the tooth, including the periodontal ligament, cementum, and the alveolar bone that surrounds and supports the tooth in the jaw.

The dental sac plays a critical role in tooth development by regulating the mineralization of the tooth crown and providing a protective environment for the developing tooth. It also contains cells called odontoblasts, which are responsible for producing dentin, one of the hard tissues that make up the tooth. Abnormalities in the development or growth of the dental sac can lead to various dental anomalies, such as impacted teeth, dilacerated roots, and other developmental disorders.

Transgenic mice are genetically modified rodents that have incorporated foreign DNA (exogenous DNA) into their own genome. This is typically done through the use of recombinant DNA technology, where a specific gene or genetic sequence of interest is isolated and then introduced into the mouse embryo. The resulting transgenic mice can then express the protein encoded by the foreign gene, allowing researchers to study its function in a living organism.

The process of creating transgenic mice usually involves microinjecting the exogenous DNA into the pronucleus of a fertilized egg, which is then implanted into a surrogate mother. The offspring that result from this procedure are screened for the presence of the foreign DNA, and those that carry the desired genetic modification are used to establish a transgenic mouse line.

Transgenic mice have been widely used in biomedical research to model human diseases, study gene function, and test new therapies. They provide a valuable tool for understanding complex biological processes and developing new treatments for a variety of medical conditions.

Vitronectin receptors, also known as integrin αvβ3 or integrin avb3, are a type of cell surface receptor that bind to the protein vitronectin. These receptors are heterodimeric transmembrane proteins composed of αv and β3 subunits. They play important roles in various biological processes including cell adhesion, migration, proliferation, and survival. Vitronectin receptors are widely expressed in many different cell types, including endothelial cells, smooth muscle cells, and platelets. In addition to vitronectin, these receptors can also bind to other extracellular matrix proteins such as fibronectin, von Willebrand factor, and osteopontin. They are also involved in the regulation of angiogenesis, wound healing, and bone metabolism.

"Wistar rats" are a strain of albino rats that are widely used in laboratory research. They were developed at the Wistar Institute in Philadelphia, USA, and were first introduced in 1906. Wistar rats are outbred, which means that they are genetically diverse and do not have a fixed set of genetic characteristics like inbred strains.

Wistar rats are commonly used as animal models in biomedical research because of their size, ease of handling, and relatively low cost. They are used in a wide range of research areas, including toxicology, pharmacology, nutrition, cancer, cardiovascular disease, and behavioral studies. Wistar rats are also used in safety testing of drugs, medical devices, and other products.

Wistar rats are typically larger than many other rat strains, with males weighing between 500-700 grams and females weighing between 250-350 grams. They have a lifespan of approximately 2-3 years. Wistar rats are also known for their docile and friendly nature, making them easy to handle and work with in the laboratory setting.

Interleukin-6 (IL-6) is a cytokine, a type of protein that plays a crucial role in communication between cells, especially in the immune system. It is produced by various cells including T-cells, B-cells, fibroblasts, and endothelial cells in response to infection, injury, or inflammation.

IL-6 has diverse effects on different cell types. In the immune system, it stimulates the growth and differentiation of B-cells into plasma cells that produce antibodies. It also promotes the activation and survival of T-cells. Moreover, IL-6 plays a role in fever induction by acting on the hypothalamus to raise body temperature during an immune response.

In addition to its functions in the immune system, IL-6 has been implicated in various physiological processes such as hematopoiesis (the formation of blood cells), bone metabolism, and neural development. However, abnormal levels of IL-6 have also been associated with several diseases, including autoimmune disorders, chronic inflammation, and cancer.

Cholecalciferol is the chemical name for Vitamin D3. It is a fat-soluble vitamin that is essential for the regulation of calcium and phosphate levels in the body, which helps to maintain healthy bones and teeth. Cholecalciferol can be synthesized by the skin upon exposure to sunlight or obtained through dietary sources such as fatty fish, liver, and fortified foods. It is also available as a dietary supplement.

Immunohistochemistry (IHC) is a technique used in pathology and laboratory medicine to identify specific proteins or antigens in tissue sections. It combines the principles of immunology and histology to detect the presence and location of these target molecules within cells and tissues. This technique utilizes antibodies that are specific to the protein or antigen of interest, which are then tagged with a detection system such as a chromogen or fluorophore. The stained tissue sections can be examined under a microscope, allowing for the visualization and analysis of the distribution and expression patterns of the target molecule in the context of the tissue architecture. Immunohistochemistry is widely used in diagnostic pathology to help identify various diseases, including cancer, infectious diseases, and immune-mediated disorders.

Titanium is not a medical term, but rather a chemical element (symbol Ti, atomic number 22) that is widely used in the medical field due to its unique properties. Medically, it is often referred to as a biocompatible material used in various medical applications such as:

1. Orthopedic implants: Titanium and its alloys are used for making joint replacements (hips, knees, shoulders), bone plates, screws, and rods due to their high strength-to-weight ratio, excellent corrosion resistance, and biocompatibility.
2. Dental implants: Titanium is also commonly used in dental applications like implants, crowns, and bridges because of its ability to osseointegrate, or fuse directly with bone tissue, providing a stable foundation for replacement teeth.
3. Cardiovascular devices: Titanium alloys are used in the construction of heart valves, pacemakers, and other cardiovascular implants due to their non-magnetic properties, which prevent interference with magnetic resonance imaging (MRI) scans.
4. Medical instruments: Due to its resistance to corrosion and high strength, titanium is used in the manufacturing of various medical instruments such as surgical tools, needles, and catheters.

In summary, Titanium is a chemical element with unique properties that make it an ideal material for various medical applications, including orthopedic and dental implants, cardiovascular devices, and medical instruments.

Tumor Necrosis Factor-alpha (TNF-α) is a cytokine, a type of small signaling protein involved in immune response and inflammation. It is primarily produced by activated macrophages, although other cell types such as T-cells, natural killer cells, and mast cells can also produce it.

TNF-α plays a crucial role in the body's defense against infection and tissue injury by mediating inflammatory responses, activating immune cells, and inducing apoptosis (programmed cell death) in certain types of cells. It does this by binding to its receptors, TNFR1 and TNFR2, which are found on the surface of many cell types.

In addition to its role in the immune response, TNF-α has been implicated in the pathogenesis of several diseases, including autoimmune disorders such as rheumatoid arthritis, inflammatory bowel disease, and psoriasis, as well as cancer, where it can promote tumor growth and metastasis.

Therapeutic agents that target TNF-α, such as infliximab, adalimumab, and etanercept, have been developed to treat these conditions. However, these drugs can also increase the risk of infections and other side effects, so their use must be carefully monitored.

Essential osteolysis is not a well-defined medical condition with a single, widely accepted medical definition. The term "osteolysis" generally refers to the loss or resorption of bone tissue. In essential osteolysis, this process occurs without an underlying cause that can be easily identified, such as a tumor, infection, or other disease.

Some sources describe essential osteolysis as a condition characterized by progressive bone loss that occurs spontaneously and symmetrically, typically affecting the small bones of the hands and feet. The exact cause of this form of osteolysis is not known, but it is thought to be related to an abnormal immune response or genetic factors.

It's important to note that essential osteolysis is a rare condition, and its symptoms and progression can vary significantly from person to person. If you have concerns about osteolysis or any other medical condition, it's best to consult with a healthcare professional for an accurate diagnosis and treatment plan.

Tooth extraction is a dental procedure in which a tooth that is damaged or poses a threat to oral health is removed from its socket in the jawbone. This may be necessary due to various reasons such as severe tooth decay, gum disease, fractured teeth, crowded teeth, or for orthodontic treatment purposes. The procedure is performed by a dentist or an oral surgeon, under local anesthesia to numb the area around the tooth, ensuring minimal discomfort during the extraction process.

Orthodontics is a specialized branch of dentistry that focuses on the diagnosis, prevention, and treatment of dental and facial irregularities. The term "corrective" in this context refers to the use of appliances (such as braces, aligners, or other devices) to move teeth into their proper position and correct malocclusion (bad bite). This not only improves the appearance of the teeth but also helps to ensure better function, improved oral health, and overall dental well-being.

The goal of corrective orthodontics is to create a balanced and harmonious relationship between the teeth, jaws, and facial structures. Treatment may be recommended for children, adolescents, or adults and can help address various issues such as crowding, spacing, overbites, underbites, crossbites, open bites, and jaw growth discrepancies. A combination of techniques, including fixed or removable appliances, may be used to achieve the desired outcome. Regular follow-up appointments are necessary throughout treatment to monitor progress and make any necessary adjustments.

A deciduous tooth, also known as a baby tooth or primary tooth, is a type of temporary tooth that humans and some other mammals develop during childhood. They are called "deciduous" because they are eventually shed and replaced by permanent teeth, much like how leaves on a deciduous tree fall off and are replaced by new growth.

Deciduous teeth begin to form in the womb and start to erupt through the gums when a child is around six months old. By the time a child reaches age three, they typically have a full set of 20 deciduous teeth, including incisors, canines, and molars. These teeth are smaller and less durable than permanent teeth, but they serve important functions such as helping children chew food properly, speak clearly, and maintain space in the jaw for the permanent teeth to grow into.

Deciduous teeth usually begin to fall out around age six or seven, starting with the lower central incisors. This process continues until all of the deciduous teeth have been shed, typically by age 12 or 13. At this point, the permanent teeth will have grown in and taken their place, with the exception of the wisdom teeth, which may not erupt until later in adolescence or early adulthood.

Mechanical stress, in the context of physiology and medicine, refers to any type of force that is applied to body tissues or organs, which can cause deformation or displacement of those structures. Mechanical stress can be either external, such as forces exerted on the body during physical activity or trauma, or internal, such as the pressure changes that occur within blood vessels or other hollow organs.

Mechanical stress can have a variety of effects on the body, depending on the type, duration, and magnitude of the force applied. For example, prolonged exposure to mechanical stress can lead to tissue damage, inflammation, and chronic pain. Additionally, abnormal or excessive mechanical stress can contribute to the development of various musculoskeletal disorders, such as tendinitis, osteoarthritis, and herniated discs.

In order to mitigate the negative effects of mechanical stress, the body has a number of adaptive responses that help to distribute forces more evenly across tissues and maintain structural integrity. These responses include changes in muscle tone, joint positioning, and connective tissue stiffness, as well as the remodeling of bone and other tissues over time. However, when these adaptive mechanisms are overwhelmed or impaired, mechanical stress can become a significant factor in the development of various pathological conditions.

The diaphysis refers to the shaft or middle portion of a long bone in the body. It is the part that is typically cylindrical in shape and contains the medullary cavity, which is filled with yellow marrow. The diaphysis is primarily composed of compact bone tissue, which provides strength and support for weight-bearing and movement.

In contrast to the diaphysis, the ends of long bones are called epiphyses, and they are covered with articular cartilage and contain spongy bone tissue filled with red marrow, which is responsible for producing blood cells. The area where the diaphysis meets the epiphysis is known as the metaphysis, and it contains growth plates that are responsible for the longitudinal growth of bones during development.

I believe there may be some confusion in your question. "Rabbits" is a common name used to refer to the Lagomorpha species, particularly members of the family Leporidae. They are small mammals known for their long ears, strong legs, and quick reproduction.

However, if you're referring to "rabbits" in a medical context, there is a term called "rabbit syndrome," which is a rare movement disorder characterized by repetitive, involuntary movements of the fingers, resembling those of a rabbit chewing. It is also known as "finger-chewing chorea." This condition is usually associated with certain medications, particularly antipsychotics, and typically resolves when the medication is stopped or adjusted.

Bone Morphogenetic Protein 6 (BMP-6) is a member of the transforming growth factor-beta (TGF-β) superfamily of proteins. It plays crucial roles in bone and cartilage formation, as well as in the regulation of iron metabolism. BMP-6 stimulates the differentiation of mesenchymal stem cells into osteoblasts, which are bone-forming cells, and contributes to the maintenance of bone homeostasis. Additionally, BMP-6 is involved in the process of hepcidin regulation, a hormone that controls iron absorption and recycling in the body. Dysregulation of BMP-6 has been implicated in various diseases, including skeletal disorders and iron metabolism-related conditions.

Phosphates, in a medical context, refer to the salts or esters of phosphoric acid. Phosphates play crucial roles in various biological processes within the human body. They are essential components of bones and teeth, where they combine with calcium to form hydroxyapatite crystals. Phosphates also participate in energy transfer reactions as phosphate groups attached to adenosine diphosphate (ADP) and adenosine triphosphate (ATP). Additionally, they contribute to buffer systems that help maintain normal pH levels in the body.

Abnormal levels of phosphates in the blood can indicate certain medical conditions. High phosphate levels (hyperphosphatemia) may be associated with kidney dysfunction, hyperparathyroidism, or excessive intake of phosphate-containing products. Low phosphate levels (hypophosphatemia) might result from malnutrition, vitamin D deficiency, or certain diseases affecting the small intestine or kidneys. Both hypophosphatemia and hyperphosphatemia can have significant impacts on various organ systems and may require medical intervention.

Tooth mobility, also known as loose teeth, refers to the degree of movement or displacement of a tooth in its socket when lateral forces are applied. It is often described in terms of grades:

* Grade 1: Tooth can be moved slightly (up to 1 mm) with finger pressure.
* Grade 2: Tooth can be moved up to 2 mm with finger pressure.
* Grade 3: Tooth can be moved more than 2 mm or can be removed from its socket with manual pressure.

Increased tooth mobility can be a sign of periodontal disease, trauma, or other dental conditions and should be evaluated by a dentist. Treatment may include deep cleaning, splinting, or surgery to restore stability to the affected teeth.

Conditioned culture media refers to a type of growth medium that has been previously used to culture and maintain the cells of an organism. The conditioned media contains factors secreted by those cells, such as hormones, nutrients, and signaling molecules, which can affect the behavior and growth of other cells that are introduced into the media later on.

When the conditioned media is used for culturing a new set of cells, it can provide a more physiologically relevant environment than traditional culture media, as it contains factors that are specific to the original cell type. This can be particularly useful in studies that aim to understand cell-cell interactions and communication, or to mimic the natural microenvironment of cells in the body.

It's important to note that conditioned media should be handled carefully and used promptly after preparation, as the factors it contains can degrade over time and affect the quality of the results.

"Edentulous jaw" is a medical term used to describe a jaw that is missing all of its natural teeth. The term "edentulous" is derived from the Latin word "edentulus," which means "without teeth." This condition can affect either the upper jaw (maxilla) or the lower jaw (mandible), or both, resulting in a significant impact on an individual's ability to eat, speak, and maintain proper facial structure.

Edentulism is often associated with aging, as tooth loss becomes more common in older adults due to factors like gum disease, tooth decay, and injury. However, it can also affect younger individuals who have lost their teeth due to various reasons. Dental professionals typically recommend the use of dentures or dental implants to restore oral function and aesthetics for patients with edentulous jaws.

Hyperparathyroidism is a condition in which the parathyroid glands produce excessive amounts of parathyroid hormone (PTH). There are four small parathyroid glands located in the neck, near or within the thyroid gland. They release PTH into the bloodstream to help regulate the levels of calcium and phosphorus in the body.

In hyperparathyroidism, overproduction of PTH can lead to an imbalance in these minerals, causing high blood calcium levels (hypercalcemia) and low phosphate levels (hypophosphatemia). This can result in various symptoms such as fatigue, weakness, bone pain, kidney stones, and cognitive issues.

There are two types of hyperparathyroidism: primary and secondary. Primary hyperparathyroidism occurs when there is a problem with one or more of the parathyroid glands, causing them to become overactive and produce too much PTH. Secondary hyperparathyroidism develops as a response to low calcium levels in the body due to conditions like vitamin D deficiency, chronic kidney disease, or malabsorption syndromes.

Treatment for hyperparathyroidism depends on the underlying cause and severity of symptoms. In primary hyperparathyroidism, surgery to remove the overactive parathyroid gland(s) is often recommended. For secondary hyperparathyroidism, treating the underlying condition and managing calcium levels with medications or dietary changes may be sufficient.

Hypocalcemia is a medical condition characterized by an abnormally low level of calcium in the blood. Calcium is a vital mineral that plays a crucial role in various bodily functions, including muscle contraction, nerve impulse transmission, and bone formation. Normal calcium levels in the blood usually range from 8.5 to 10.2 milligrams per deciliter (mg/dL). Hypocalcemia is typically defined as a serum calcium level below 8.5 mg/dL or, when adjusted for albumin (a protein that binds to calcium), below 8.4 mg/dL (ionized calcium).

Hypocalcemia can result from several factors, such as vitamin D deficiency, hypoparathyroidism (underactive parathyroid glands), kidney dysfunction, certain medications, and severe magnesium deficiency. Symptoms of hypocalcemia may include numbness or tingling in the fingers, toes, or lips; muscle cramps or spasms; seizures; and, in severe cases, cognitive impairment or cardiac arrhythmias. Treatment typically involves correcting the underlying cause and administering calcium and vitamin D supplements to restore normal calcium levels in the blood.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

Estrogens are a group of steroid hormones that are primarily responsible for the development and regulation of female sexual characteristics and reproductive functions. They are also present in lower levels in males. The main estrogen hormone is estradiol, which plays a key role in promoting the growth and development of the female reproductive system, including the uterus, fallopian tubes, and breasts. Estrogens also help regulate the menstrual cycle, maintain bone density, and have important effects on the cardiovascular system, skin, hair, and cognitive function.

Estrogens are produced primarily by the ovaries in women, but they can also be produced in smaller amounts by the adrenal glands and fat cells. In men, estrogens are produced from the conversion of testosterone, the primary male sex hormone, through a process called aromatization.

Estrogen levels vary throughout a woman's life, with higher levels during reproductive years and lower levels after menopause. Estrogen therapy is sometimes used to treat symptoms of menopause, such as hot flashes and vaginal dryness, or to prevent osteoporosis in postmenopausal women. However, estrogen therapy also carries risks, including an increased risk of certain cancers, blood clots, and stroke, so it is typically recommended only for women who have a high risk of these conditions.

  • Bone resorption is resorption of bone tissue, that is, the process by which osteoclasts break down the tissue in bones and release the minerals, resulting in a transfer of calcium from bone tissue to the blood. (
  • High levels of calcium, magnesium, phosphate and products of collagen will be released into the extracellular fluid as the osteoclasts tunnel into the mineralized bone. (
  • Bone is resorbed by osteoclasts, and is deposited by osteoblasts in a process called ossification. (
  • High levels of calcium in the blood, on the other hand, leads to decreased PTH release from the parathyroid gland, decreasing the number and activity of osteoclasts, resulting in less bone resorption. (
  • Calcitonin decreases osteoclast activity, and decreases the formation of new osteoclasts, resulting in decreased resorption. (
  • In contrast, TNF often acts on cell types other than osteoclasts, or synergically with RANKL to indirectly promote osteoclastogenesis and bone resorption. (
  • Normal bone remodeling requires a delicate balance between the activities of major bone cell types: bone-resorbing osteoclasts and bone-forming osteoblasts, as well as osteocytes. (
  • Osteoclasts are bone cells derived from monocyte/macrophage lineage and are exclusively responsible for bone resorption, which contributes to skeletal development, bone homeostasis, and remodeling. (
  • Osteoclasts break down old bone and deliver it into your bloodstream (resorption), and osteoblasts build your bone where it needs to be reinforced (ossification). (
  • If you're missing a tooth due to tooth extraction, gum disease, or injury, the jawbone in the area of loss no longer receives stimuli, osteoclasts will begin to break down the jawbone, and osteoblasts will no longer prioritise rebuilding the bone structure there. (
  • Estrogen inhibits bone resorption by directly +6inducing apoptosis of the bone-resorbing osteoclasts. (
  • In this study, we show that human Btk-deficient osteoclasts are defective at resorption activity in vitro owing to a dysregulation of the actin cytoskeletal function. (
  • This study provides novel evidence that Btk signaling is crucial for optimal actin cytoskeletal organization and lacunar resorption in isolated osteoclasts. (
  • Bone resorption depends on the secretion of proton and procathepsin L from osteoclasts into the extracellular lacunae. (
  • The proton is generated by carbonic anhydrase II in osteoclasts and activity in the lacunae by a proton pump driven by vacuolar-type H + -ATPase at the ruffled border, and the secreted proton participates in the bone resorption. (
  • Special cells called osteoclasts, break down old bone and release important nutrients into our bloodstream. (
  • Osteoclasts are multinucleated phagocytic cells that degrade bone to initiate normal bone remodeling and control bone loss by increasing their resorptive activity. (
  • In this blog we will explore the procedure by which osteoclasts-specialized cells within our skeletal system-break down the tissue in bones and release the minerals, resulting in a transfer of calcium from bone fluid to the blood. (
  • Osteoclasts play a key role in the process of bone resorption. (
  • Osteoclasts orginate from the fusion of macrophage-like cells in the bone marrow. (
  • Here, osteoclasts secrete hydrogen ions and enzymes like cathepsin K to dissolve the bone's mineral matrix, facilitating the breakdown and resorption of bone tissue. (
  • However, when the activity of these bone-resorbing osteoclasts exceeds that of the bone-depositing osteoblasts, bone loss occurs, which could lead to conditions such as osteoporosis . (
  • The process of bone resorption, as we have learned, is driven by osteoclasts. (
  • Bone resorption occurs mainly on the bone surface, by the osteoclasts (OC) on bone metabolism in continuous absorption. (
  • It inhibits bone resorption via actions on osteoclasts or osteoclast precursors. (
  • RANKL-responsive epigenetic mechanism reprograms macrophages into bone-resorbing osteoclasts. (
  • Cell fusion -mediated formation of multinuclear osteoclasts (OCs) plays a key role in bone resorption . (
  • Bone resorption is the normal destruction of bone by osteoclasts, which are indirectly stimulated by PTH. (
  • Bones were examined for ED1-immunoreactive mononuclear cells and osteoclasts. (
  • Increases in ED1+ mononuclear cells and osteoclasts indicate that highly repetitive , negligible force reaching causes pathological overloading of bone leading to inflammation and osteolysis of periosteal bone tissues. (
  • The longer the duration of menopause, the more estradiol function decreases, which causes osteoclasts to become active in bone resorption [3]. (
  • Digital images were obtained and the alveolar bone loss was measured (mm²) using an image analysis software. (
  • In our mouse model, systemic administration of anti-OC-STAMP-mAb suppressed the expression of CD9 mRNA , but not DC-STAMP mRNA , in periodontal tissue , along with diminished alveolar bone loss and reduced emergence of CD9+ OCps and tartrate-resistant acid phosphatase -positive multinuclear OCs. (
  • Alveolar bone height was measured using Proximal RABL (Radiographic Alveolar Bone Loss) method with the help of Ez-Pax Plus software. (
  • Some diseases with symptoms of decreased bone density are osteoporosis, and rickets. (
  • Through direct and indirect pathways, prolonged ethanol exposure increases fracture risk by decreasing bone mineral density and promoting osteoporosis. (
  • Under inflammatory conditions, abnormal osteoclast differentiation and function often results in excessive bone resorption, which is a common characteristic of many diseases, such as osteoporosis, rheumatoid arthritis (RA), psoriatic arthritis and periodontitis ( 1 - 5 ). (
  • Diagnosis of osteoporosis is not based on evaluation of bone markers, and BMD assessment is still the criterion standard for evaluation and diagnosis. (
  • However, mean values for markers of bone turnover are higher in patients with osteoporosis than in the matched controls. (
  • [ 6 ] Therefore, measurement of bone markers is not recommended to make a diagnosis of osteoporosis. (
  • According to the Ministry of Health and Family Welfare , osteoporosis refers to a disease characterised by extremely fragile and less dense bones. (
  • Since both osteoporosis and periodontal diseases are bone resorptive diseases, it has been hypothesised that osteoporosis could be a risk factor for the progression of periodontal disease. (
  • Many things can speed up bone resorption including changes in our hormones (especially in women after menopause) to certain health conditions like osteoporosis, and even aging. (
  • Osteoporosis, rheumatoid arthritis, and certain cancers can cause rapid bone resorption. (
  • Based on previous studies, this review will summarize the regulatory network mechanism of ferroptosis on bone remodeling and reveal the role of ferroptosis in osteoporosis (OP). (
  • Osteoporosis (OP) is a metabolic disorder, which is characterized by the decrease of bone mass, and the increase of bone brittleness ( 1 ). (
  • The imbalance of bone formation and resorption is considered the main mechanism of osteoporosis. (
  • The compositions of the invention are useful for the treatment or prophylaxis of diseases or conditions which are characterized by increased bone resorption, such as Paget's disease, tumor-induced bone disease or particularly osteoporosis. (
  • We now have more agents than ever before to treat osteoporosis, including newer anabolic drugs such as teriparatide, abaloparatide, and romosozumab that increase bone formation and are extremely effective at preventing fractures. (
  • 2 The International Osteoporosis Foundation has proposed that the serum CTX level be used as a reference marker of bone resorption and that procollagen type 1 be used as a reference for bone formation. (
  • Markers of bone resorption are elevated in situations where there is greater bone resorption than bone formation, such as in postmenopausal osteoporosis, although, as Ashcherkin and colleagues point out, 1 an elevated marker of resorption is hardly specific for postmenopausal osteoporosis and can be seen in a variety of disease states. (
  • Pharmacologic therapy for osteoporosis includes most commonly the use of antiresorptive agents to decrease bone resorption, such as bisphosphonates, denosumab, and the selective estrogen-receptor modulator (SERM) raloxifene. (
  • Calcitonin is used for the treatment of postmenopausal osteoporosis in women more than 5 years post menopause with low bone mass relative to healthy premenopausal females. (
  • Osteoporosis (OP) is a skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue, leading to increased susceptibility to fractures (World Health Organization, 1994). (
  • Uncoupling of bone formation and resorption by combined o estrogen and progestagen therapy in postmenopausal osteoporosis. (
  • Although it does not cause death, menopause can decrease quality of life and lead to degenerative diseases especially bone loss or osteoporosis [2]. (
  • Osteoporosis is characterized by bone mineral density (BMD), thus increasing bone fragility and fracture risk. (
  • Common treatments include drugs that increase bone mineral density. (
  • Ossification decreases due to a lack of stress, while resorption increases, leading to a net decrease in bone density. (
  • The effects of alcohol on bone mineral density (BMD) are well-known and well-studied in animal and human populations. (
  • Such markers can also be useful in selected cases to improve the assessment of individual fracture risk when bone mineral density (BMD) measurement by itself does not provide a clear answer. (
  • Contrary to expectation, XLA patients did not exhibit increased bone density or alterations in serum markers of bone turnover, indicating that a potential compensation mechanism normalizes bone homeostasis. (
  • In XLA patients, however, these inherent osteoclast defects are corrected by increased inflammatory cytokine levels, restoring osteoclast activity and leading to the normalization of bone density. (
  • Bone mineral density (BMD) of femur and spine was assessed by dual-energy X-ray absorptiometry (DXA). (
  • Smoking can reduce bone density and increase the risk of fractures, potentially due to increased bone resorption. (
  • Smoking decreases bone density and increase the risk of fractures. (
  • Especially for those at risk, regular bone density tests can help in the early detection of increased bone resorption, allowing for early intervention. (
  • Background: Pre-exposure prophylaxis (PrEP) with emtricitabine (FTC)/tenofovir disoproxil fumarate (TDF) reduces the risk of HIV seroconversion but may promote bone mineral density (BMD) decline. (
  • The relatively rapid decrease in markers of bone resorption (within days of intravenous or injection therapy, and within weeks to months of initiating oral therapy) lies in stark contrast to the slower, less dramatic changes observed on bone density scans. (
  • 4 - 6 In addition to providing information on bone resorption or formation, BTMs are useful in that they can be measured more frequently than bone density scans can be obtained, therefore providing the clinician with more real-time data to aid decision-making. (
  • In contrast to DC-STAMP-knockout (KO) mice , which show the osteopetrotic phenotype , OC-STAMP-KO mice show no difference in systemic bone mineral density . (
  • QCT and pQCT offer the advantage of measuring the volumetric density of bones. (
  • Evaluation of bone mineral status can utilize measures of total bone mineral content and bone mineral density. (
  • If sustained, this pattern of BTM uncoupling may lead to bone loss and lower bone mineral density. (
  • Introduction: Previous bone density studies have generally shown bone resorption around both cemented and uncemented total hip arthroplasty (THA) stems. (
  • To analyze the relationship between age, body mass index (BMI), bone mineral density (BMD), and alveolar bone resorption with menopause duration in postmenopausal women. (
  • The longer the duration of menopause showed a tendency for lower bone density and higher age, BMI, and bone resorption. (
  • There are a number of factors that can speed up the process of bone resorption. (
  • Pamidronate inhibits both normal and abnormal bone resorption. (
  • Alendronate inhibits osteoclast activity and bone resorption. (
  • By binding to calcium salts, alendronate blocks the transformation of calcium phosphate into hydroxyapatite and inhibits the formation, aggregation, and dissolution of hydroxyapatite crystals in bone. (
  • It inhibits osteoclastic bone resorption and has some analgesic effects in patients with fractures. (
  • Osteoblasts are generally present on the outer layer of bone, just beneath the periosteum. (
  • For your jawbone, when you chew and bite, the force you exert through your teeth into your jaws sends signals to osteoblasts to keep that bone strong. (
  • Intermittent injections of parathyroid hormone (iPTH) are applied clinically to stimulate bone formation by osteoblasts, although continuous elevation of parathyroid hormone (PTH) primarily results in increased bone resorption. (
  • This complex process is often paired with bone deposition, another critical physiological process performed by osteoblasts that aids in bone formation and repair. (
  • It involves the creation and mineralization of new bone tissue, a task performed by cells called osteoblasts. (
  • Bone formation is involved with a large number of osteoblasts (OB) under the periosteum. (
  • rather, PTH binds to osteoblasts, the cells responsible for creating bone. (
  • Bisphosphonates have a high affinity for hydroxyapatite crystals, and by binding at sites of active bone resorption, these agents can inhibit osteoclastic resorption. (
  • Increased blood flow to bone from reflex vasodilation, resulting in active bone resorption, contributes to bone and joint damage. (
  • Long-term use of certain medications, like corticosteroids, can increase bone resorption. (
  • Some people who experience increased bone resorption and decreased bone formation are astronauts. (
  • OB release bone matrix rich in collagen type I and participate in the hydroxyapatite crystal formation in collagen fiber deposition process, namely bone mineralization process, eventually forming new bone. (
  • It appears to inhibit bone resorption without as much impact on bone formation and mineralization. (
  • Risedronate is a potent antiresorptive agent that does not affect bone mineralization. (
  • Bone resorption rates are much higher in post-menopausal older women due to estrogen deficiency related with menopause. (
  • Sowers and colleagues have investigated potential associations between changes in bone resorption during the menopause transition and reproductive hormones, body mass index (BMI) and ethnicity [1]. (
  • During the menopause transition, a decline in ovarian function beginning about 2 years before the FMP is followed by an increase in bone resorption and subsequently by bone loss. (
  • Changes in bone resorption across the menopause transition: effects of reproductive hormones, body size, and ethnicity. (
  • Menopause causes decreased levels of circulating estrogens which often results in rapid bone loss. (
  • Various biochemical markers are now available that allow a specific and sensitive assessment of the rate of bone formation and bone resorption of the skeleton. (
  • CONCLUSION: OS could play an important role in PO development by increasing the rate of bone resorption. (
  • As people age the rate of bone resorption generally increases. (
  • Interestingly, the location and rate of bone deposition are directly influenced by the demands placed on the skeleton. (
  • Normoxic inducers of HIF (CoCl(2), desferrioxamine, and l-mimosine) and 100 ng/ml ANGPTL4 stimulated osteoclastic resorption 2- to 3-fold in assays of lacunar dentine resorption, without affecting osteoclast viability. (
  • Decreases in estrogen levels can accelerate bone resorption. (
  • Hormone replacement therapy (eg, estrogen, estrogen analogs) does not have a role in pediatric therapy unless the low bone mass is attributable to hypogonadism. (
  • Biochemical monitoring of bone metabolism depends upon measurement of enzymes and proteins released during bone formation and of degradation products produced during bone resorption. (
  • Alkaline phosphatase has been clinically available for several years as a marker for bone metabolism. (
  • In particular, evidences suggest that oxygen reactive species (ROS) are able to influence the balance between bone resorption and formation, responsible for PO is involved in bone metabolism and PO development. (
  • Bone is an active metabolism tissue, which constantly undergoes bone remodeling. (
  • We evaluated the impact of FTC/TDF on biomarkers of bone remodeling and bone mineral metabolism in HIV-negative men and women enrolled in the Partners PrEP Study. (
  • Conclusions: These pilot data are similar to previous findings in men and suggest that SRCD negatively altered bone metabolism in women by decreasing markers of bone formation and, in young women, increasing a marker of bone resorption. (
  • The bone becomes more porous and fragile, exposing people to the risk of fractures. (
  • The combined use of BMD measurement and bone markers is likely to improve the assessment of the risk of fractures in those cases. (
  • But when resorption happens at a higher rate than it can be replaced, it can lead to a decrease in your bone mass and put you at higher risk for fractures and breakage. (
  • In certain severe cases-like when there is significant bone loss leading to fractures or other structural problems-surgery may be necessary. (
  • Open 4-year postdoc position for the project "How bisphosphonates affect bone matrix and remodeling: implications for atypical femoral fractures" within my Molecular Bone Histology (MBH) lab, Denmark. (
  • Fractures and bony healing may produce many loose pieces of cartilage or bone that can slough into the joint, causing a coarse, grating, often audible crepitus usually more unpleasant for the observer than for the patient. (
  • It follows that an increase in vitamin D3 intake should lead to a decrease in bone resorption - it has been shown that oral administration of vitamin D does not linearly correlate to increased serum levels of calcifediol, the precursor to calcitriol. (
  • Serum osteocalcin is considered a specific marker of osteoblast function, as its levels correlate with the bone formation rate. (
  • Low doses of IGF-I constituted a real replacement therapy that normalized IGF-I serum levels improving the expression of most of these proteins closely involved in bone-forming, and reducing bone resorption by mechanisms related to osteoprotegerin, RANKL and PTH receptor. (
  • In contrast to the bone turnover markers, the levels of inflammatory cytokines interleukin 6 (IL-6), IL-1β, and tumor necrosis factor α (TNF-α) were significantly elevated in XLA patients' serum compared with control individuals. (
  • The bone health status was also evaluated by assessing serum levels of bone alkaline phophatase (BAP) and collagen type 1 cross-linked C-telopeptide (CTX-1), markers of bone formation and resorption, respectively. (
  • Methods: In a random sample of HIV-negative participants randomized to FTC/TDF PrEP (n = 50) or placebo (n = 50), serum parathyroid hormone (PTH), bone biomarkers (C-telopeptide, procollagen 1 intact N-terminal propeptide, and sclerostin), and plasma fibroblast growth factor 23 were measured at baseline and month 24, and the percentage change was compared between groups. (
  • We observed a significantly greater percent increase in serum C-telopeptide in participants randomized to FTC/TDF vs placebo (P =. 03), suggesting an increase in bone remodeling. (
  • Serum bone alkaline phosphatase is a marker of bone formation and urinary N-telopeptides are markers of bone resorption. (
  • For NHANES 2001, the HybritechTandem-MP Ostase ImmunoEnzymetric assay was used for quantitative measurement of Bone Alkaline Phosphatase (BAP), an indicator of osteoblastic activity, in human serum. (
  • Markers of both bone formation and bone resorption can be used clinically, and many clinicians, myself included, use markers of bone formation such as procollagen type 1 to assess a patient's response to an anabolic agent such as teriparatide, abaloparatide, or romosozumab. (
  • Therefore, the purpose of the clinical series presented herein was to clinically evaluate long-term horizontal and vertical bone gain, as well as implant survival rate after reconstruction of severely atrophic edentulous maxillary ridges. (
  • The degree of bone resorption was classified clinically using with radiologic and operation findings. (
  • Conditions that result in a decrease in bone mass can either be caused by an increase in resorption or by a decrease in ossification. (
  • These agents decrease bone resorption and prevent bone loss from diminishing bone mass on an ongoing basis. (
  • Conclusions: Increased bone remodeling may mediate the BMD decline observed with tenofovir-containing PrEP and antiretroviral therapy, independent of a TDF-mediated decrease in kidney function. (
  • As the aging process occurs, resorption exceeds formation. (
  • Depending on where in the body bone resorption occurs, additional problems like tooth loss can arise. (
  • If bone resorption occurs in the implant crest module, the gingival margin is in a more apical position (5, 6). (
  • Purpose: The purpose of this work is to determine whether an uncoupling of bone turnover markers (BTMs) occurs in women exposed to the combination of sleep restriction with circadian disruption (SRCD), as previously reported in men. (
  • The value of these byproducts of osteoclastic activity lies in the observation that bone turnover decreases in response to treatment with antiresorptive agents such as bisphosphonates. (
  • Current treatments for excessive bone resorption utilize RANK receptor blockers or neutralizing antibodies, which are able to inhibit osteoclast formation. (
  • During iPTH treatment, mice lacking ProCT develop increased bone resorption with excessive osteoclast formation in both the long bones and axial skeleton. (
  • Regular exercise, a healthy diet, and avoiding smoking and excessive drinking can keep our bones strong. (
  • Excessive alcohol interferes with the balance of calcium in the body and affect bone health. (
  • Excessive bone resorption is found in most dental patients with gum disease and multiple tooth loss. (
  • Hence, discovery of these intrinsic inhibitory mechanisms addresses why TNF has a weak osteoclastogenic potential, explains a significant difference between RANKL and TNF signaling, and provides potentially new or complementary therapeutic strategies to selectively treat inflammatory bone resorption, without undesirable effects on normal bone remodeling or immune response in disease settings. (
  • Understanding the mechanistic difference between RANKL-mediated physiological and TNF-mediated inflammatory osteoclastogenesis, and especially TNF-induced intrinsic inhibitory mechanisms, will strengthen the development of therapeutic approaches to treat pathological bone destruction in disease settings and prevent negative side effects on bone remodeling and immunity. (
  • Waif1 cKO mice exhibited impaired bone mass recovery after RANKL injections, phenocopying osteoclast-specific Cthrc1 cKO mice. (
  • Osteogenesis Imperfecta and Paget's disease are examples of factors that can cause bone resorption. (
  • However, inhibition of osteoclast formation via blocking RANK signaling can result in long-term bone remodeling defects. (
  • Their major pharmacologic action is the inhibition of bone resorption. (
  • Using topical antibiotics did not affect bone resorption after three months of implant placement. (
  • How does the release of PTH affect bone resorption? (
  • Bone resorption is a fundamental biological process, instrumental in the maintenance of skeletal integrity and calcium homeostasis within our bodies. (
  • Bone resorption and deposition are interlinked processes, integral to the ongoing remodeling of our skeletal system. (
  • Skeletal manifestations include a selective cortical bone loss. (
  • The main target organs where parathyroid hormone exerts its effects are the bones and the kidneys. (
  • The primary response to parathyroid hormone (PTH) by the kidney is to increase renal calcium resorption and phosphate excretion. (
  • The classical target organs for parathyroid hormone (PTH) are the bone and kidneys. (
  • The main effects of parathyroid hormone are to increase the concentration of plasma calcium by increasing the release of calcium and phosphate from bone matrix, increasing calcium reabsorption by the kidney, and increasing renal production of 1,25-dihydroxyvitamin D-3 (calcitriol), which increases intestinal absorption of calcium. (
  • Further, there are signaling pathways that participate in regulation, such as Wnt channel, mitogen-activated protein kinase (MAPK) channel, bone morphogenetic protein (BMPs) channel, peroxisome proliferator activated-receptors (PPARs) channel, and Notch channel. (
  • Journal Article] WAIF1 is a cell-surface CTHRC1 binding protein coupling bone resorption and formation. (
  • Calcitonin has a greater effect in young children than in adults, and plays a smaller role in bone remodeling than PTH. (
  • Use of calcitonin-salmon injection is recommended in conjunction with adequate calcium and vitamin D intake to prevent the progressive loss of bone mass. (
  • The phrase "bone turnover" encapsulates markers of bone resorption and markers of bone formation. (
  • likewise, markers of bone formation are byproducts of osteoblastic activity in bone that are released when bone is formed. (
  • These results demonstrate that HIF is sufficient to enhance osteoclast-mediated bone resorption and that ANGPTL4 can compensate for HIF-1α deficiency with respect to stimulation of osteoclast activity and also augments osteoblast proliferation and differentiation. (
  • They break down bone tissue and release the stored minerals back into the bloodstream. (
  • As discussed by Ashcherkin and colleagues, 1 BTMs are byproducts of bone remodeling released into the bloodstream. (
  • In conclusion, our results reveal a potential role of osteoblast-derived ProCT in the bone microenvironment that is required to limit bone resorption during iPTH. (
  • Conclusion: In this study, raloxifene did not inhibit alveolar bone resorption following MFS in male mice. (
  • Conclusion: Alveolar bone height in partially edentulous mandible of female patients underwent resorption of mild classification according to proximal RABL method. (
  • Conclusion: Cytokines may play a role in the bone resorption in aural cholesteatoma. (
  • Conclusion: This short stem seems to preserve proximal bone stock up to 5 years, exhibiting similar behaviour both with and without a collar. (
  • These cells synthesize new bone matrix by laying down collagen fibers and promoting the deposition of mineral crystals within these fibers. (
  • OC destroys the mineral and collagen matrix by secreting matrix metalloproteinases (MMPs), cathepsin K (CtsK), H + and Cl − , and eventually forming bone lacunae. (
  • Markers of bone resorption include collagen breakdown products C-terminal telopeptide of type I collagen (CTX) and N-terminal telopeptide of type I collagen (NTX), noncollagen proteins, osteoclastic enzymes, and osteocyte activity markers. (
  • Vitamin D increases absorption of calcium and phosphate in the intestinal tract, leading to elevated levels of plasma calcium, and thus lower bone resorption. (
  • According to the Indian Dental Association , gingivitis is an entry level form of periodontal disease, which attacks the gum tissue and eventually works its way to the jaw bone and causes permanent damage including loss of teeth. (
  • Bone is a dynamic tissue with high remodeling capacity in response to the body's metabolic requirements. (
  • The studies conducted on dental implants over several years have demonstrated that the long-term success of implants depends on two factors: first, the direct relationship between bone and implants, and second, the development of soft and hard tissue around the coronal area of ​​the implant (1-3). (
  • In the presence of proper plaque control, the attachment of soft tissue in the coronal area of ​​the implant creates a suitable biological seal that prevents the penetration of microorganisms and bone resorption in the area adjacent to the implant. (
  • It is also involved in bone resorption, the breakdown and removal of bone tissue that is no longer needed. (
  • These are the cells responsible for the resorption of bone. (
  • Your bones have two kinds of cells that do all the work to remodel your skeleton as needed. (
  • These unique, bone-resorbing cells have a primary function - to maintain and remodel bone structure. (
  • These multinucleated, giant cells attach to the bone surface, forming a specialized cell-to-bone contact area known as the 'sealing zone. (
  • These results provide evidence for Waif1 on stromal/osteoblastic cells as a receptor of osteoclast-secreted Cthrc1, and suggest that Waif1 serves an important coupling function of bone resorption to formation. (
  • TNF (Tumor necrosis factor) is a pleiotropic cytokine that plays an important role in immunity and inflammatory bone destruction. (
  • In addition, there were also significant differences of these cytokine levels between the group of chronic otitis media with bone resorption and the group without bone resorption. (
  • Cholesteatoma;Cytokine;Bone resorption. (
  • Adapted from Ross PD, Knowlton W. Rapid bone loss is associated with increased levels of biochemical markers. (
  • The present work extends this model so as to describe the rapid bone resorption observed, for example, in mandibulae around artificial implants. (
  • Further, it regulates osteoblastic extracellular matrix such as osteopontin (OPN), osteocalcin (OCN), bone sialoprotein (BSP) in late differentiation. (
  • The field of bone turnover markers has developed considerably in the past decade. (
  • In this issue of the Cleveland Clinic Journal of Medicine , Ashcherkin and colleagues 1 review how bone turnover markers (BTMs) can be used to monitor oral bisphosphonate treatment efficacy and patient adherence. (
  • However, the clinical applications of bone turnover markers (BTMs) can extend beyond these roles: BTMs can be utilized to determine when to start or end a bisphosphonate "holiday," and they can also measure treatment response. (
  • Sleep restriction with circadian disruption negatively alter bone turnover markers in women. (
  • Low bone mass in the skeleton, which increases the risk of osteoporotic fracture, also may be associated with periodontal bone loss and tooth loss. (
  • Often, we don't realize our bones are getting weaker until we suffer a fracture or persistent back pain as an example. (
  • Bisphosphonate Withdrawal: Effects on Bone Formation and Bone Resorption in Maturing Male Mice. (
  • Nonetheless, according to the ligature -induced periodontitis model, significantly lower level of bone resorption was found in OC-STAMP-KO mice compared to WT mice . (
  • Osteoblast-specific Waif1 cKO mice showed a high bone mass with reduction of both bone formation and resorption. (
  • This leads to a greater resorption of calcium and phosphate ions. (
  • Inflammatory conditions have complex impacts on osteoclastogenesis and bone remodeling ( 1 , 5 , 6 ). (
  • Local ablation of TRPV1 eliminated facial heat hyperalgesia but aggravated alveolar bone damage and osteoclastogenesis in experimental periodontitis in both diabetic and non-diabetic rats. (
  • T cell activation was reported to induce expression of this gene and lead to an increase of osteoclastogenesis and bone loss. (
  • The present study demonstrated that OC-STAMP partners CD9 to promote periodontal bone destruction by up-regulation of fusion during osteoclastogenesis , suggesting that anti-OC-STAMP-mAb may lead to the development of a novel therapeutic regimen for periodontitis . (
  • In adults with normal liver function, approximately 50% of the total alkaline phosphatase activity arises from the liver and 50% from the bone. (
  • The development of immunoassay-based markers with monoclonal antibodies directed to the bone-specific isoform of alkaline phosphatase has improved specificity and sensitivity. (
  • Changes in bone-specific alkaline phosphatase can lag by several weeks. (
  • Bone alkaline phosphatase Participants aged 16-69 years were tested. (
  • There were two methods used to measure Bone Alkaline Phosphatase in NHANES 2001-2002. (
  • Bone remodeling is a process which maintains bone strength and ion homeostasis by replacing discrete parts of old bone with newly synthesized packets of proteinaceous matrix. (
  • Adult skeleton undergoes constant remodeling throughout life to maintain bone homeostasis. (
  • We aimed to investigate the contribution of neurons expressing transient receptor potential vanilloid subtype 1 (TRPV1) to alveolar bone homeostasis in periodontitis with diabetes. (
  • Osteolysis and bone resorption are two concepts that often surface in discussions about bone health, and for good reason - they are closely interconnected. (
  • While this definition might sound similar to bone resorption, osteolysis often implies a pathological process, whereas bone resorption can be both a normal physiological process and a pathological one. (
  • In addition to the symptoms noted above, jawbone loss can cause you to lose teeth and make it difficult or impossible to give you replacement teeth (implants, removable bridges, or dentures) without an oral surgeon first performing a bone graft. (
  • When bone resorption in the jawbone has become so severe, a full mouth rehabilitation is usually required in order to bring the jawbone, teeth and gums back to a healthy, functional state and restore the patient's oral health and comfort. (
  • In cases of jawbone resorption, for example, bone grafting could be considered. (
  • Prediction of bone loss with biochemical bone markers. (
  • You may not notice the early stages of bone loss in your jaw. (
  • What Causes Bone Loss in the Jaw? (
  • If you wear dentures and they've become loose, it may be a result of bone loss, and they may require refitting. (
  • A research study published in the Journal of Research in Medical and Dental Science revealed that there was vertical bone loss in the interproximal area after orthodontic treatment done both with and without extraction of the teeth. (
  • Ethnic differences in BMI, and corresponding ethnic differences in bone resorption, appear to account for much of the ethnic variation in perimenopausal bone loss. (
  • Pei L, Tontonoz P. Fats loss is bones gain. (
  • Bone loss due to osteoclastic activity. (
  • Raloxifene is an agonist in bone, and acts inhibiting bone loss. (
  • During the dissection process, the periosteum is detached from the alveolar bone, leading to a resorptive phase due to the stimulation offered by osteoclastic activity and loss of bone crest 2-4 . (
  • Implant survival, bone gain, intraoperative/postoperative complications and peri-implant bone loss were calculated up to the last follow-up exam. (
  • Mean peri-implant bone loss values were consistent within the standards for implant success (1.4 ± 1.0 mm). (
  • At patient-level, only one patient who had three implants presented with severe peri-implant bone loss. (
  • The presence of peri-implant inflammation can lead to the loss of implant if extended to the bone. (
  • It usually involves bone loss because of cessation of ovarian production of estrogens in women. (
  • Bone loss seen on radiography was measured by drawing a vertical line from the cementoenamel in the distal part of the 36 teeth and the mesial portion of 46 teeth to the base of the bone marked by the lamina dura intact. (
  • BMD changes that occur with increasing age are thought to be related to the decline in osteoblastic (bone formation) function (Mahan & Escott-Stomp, 2004). (
  • Background and Objectives : Cytokines are reported to play an important role in bone resorptive process in chronic otitis media with or without aural cholesteatoma. (
  • Maximum likelihood estimation in a repeated-measures model was used to assess the effects of SRCD and age on bone biomarkers. (

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