The upper part of the tooth, which joins the lower part of the tooth (TOOTH ROOT) at the cervix (TOOTH CERVIX) at a line called the cementoenamel junction. The entire surface of the crown is covered with enamel which is thicker at the extremity and becomes progressively thinner toward the cervix. (From Jablonski, Dictionary of Dentistry, 1992, p216)
Orthodontic techniques used to correct the malposition of a single tooth.
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)
Cylindrical epithelial cells in the innermost layer of the ENAMEL ORGAN. Their functions include contribution to the development of the dentinoenamel junction by the deposition of a layer of the matrix, thus producing the foundation for the prisms (the structural units of the DENTAL ENAMEL), and production of the matrix for the enamel prisms and interprismatic substance. (From Jablonski's Dictionary of Dentistry, 1992)
A hard thin translucent layer of calcified substance which envelops and protects the dentin of the crown of the tooth. It is the hardest substance in the body and is almost entirely composed of calcium salts. Under the microscope, it is composed of thin rods (enamel prisms) held together by cementing substance, and surrounded by an enamel sheath. (From Jablonski, Dictionary of Dentistry, 1992, p286)
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)
Partial or complete displacement of a tooth from its alveolar support. It is commonly the result of trauma. (From Boucher's Clinical Dental Terminology, 4th ed, p312)
Measurement of tooth characteristics.
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)
The tip or terminal end of the root of a tooth. (Jablonski, Dictionary of Dentistry, 1992, p62)
Such malposition and contact of the maxillary and mandibular teeth as to interfere with the highest efficiency during the excursive movements of the jaw that are essential for mastication. (Jablonski, Illustrated Dictionary of Dentistry, 1982)
Break or rupture of a tooth or tooth root.
Root Canal Therapy
A treatment modality in endodontics concerned with the therapy of diseases of the dental pulp. For preparatory procedures, ROOT CANAL PREPARATION is available.
Wires of various dimensions and grades made of stainless steel or precious metal. They are used in orthodontic treatment.
The curve formed by the row of TEETH in their normal position in the JAW. The inferior dental arch is formed by the mandibular teeth, and the superior dental arch by the maxillary teeth.
An extra tooth, erupted or unerupted, resembling or unlike the other teeth in the group to which it belongs. Its presence may cause malposition of adjacent teeth or prevent their eruption.
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 process of TOOTH formation. It is divided into several stages including: the dental lamina stage, the bud stage, the cap stage, and the bell stage. Odontogenesis includes the production of tooth enamel (AMELOGENESIS), dentin (DENTINOGENESIS), and dental cementum (CEMENTOGENESIS).
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)
Reinsertion of a tooth into the alveolus from which it was removed or otherwise lost.
Photographic techniques used in ORTHODONTICS; DENTAL ESTHETICS; and patient education.
Orthodontic Appliance Design
The teeth of the first dentition, which are shed and replaced by the permanent teeth.
The elaboration of dental enamel by ameloblasts, beginning with its participation in the formation of the dentino-enamel junction to the production of the matrix for the enamel prisms and interprismatic substance. (Jablonski, Dictionary of Dentistry, 1992).
Malocclusion, Angle Class II
Dental Pulp Necrosis
The surgical removal of a tooth. (Dorland, 28th ed)
Traumatic or other damage to teeth including fractures (TOOTH FRACTURES) or displacements (TOOTH LUXATION).
Tooth Eruption, Ectopic
An abnormality in the direction of a TOOTH ERUPTION.
Orthodontic movement in the coronal direction achieved by outward tension on the PERIODONTAL LIGAMENT. It does not include the operative procedure that CROWN LENGTHENING involves.
Dental Pulp Cavity
The space in a tooth bounded by the dentin and containing the dental pulp. The portion of the cavity within the crown of the tooth is the pulp chamber; the portion within the root is the pulp canal or root canal.
The relationship of all the components of the masticatory system in normal function. It has special reference to the position and contact of the maxillary and mandibular teeth for the highest efficiency during the excursive movements of the jaw that are essential for mastication. (From Jablonski, Dictionary of Dentistry, 1992, p556, p472)
Orthodontic Space Closure
Post and Core Technique
Malocclusion, Angle Class I
Epithelial cells surrounding the dental papilla and differentiated into three layers: the inner enamel epithelium, consisting of ameloblasts which eventually form the enamel, and the enamel pulp and external enamel epithelium, both of which atrophy and disappear before and upon eruption of the tooth, respectively.
The length of the face determined by the distance of separation of jaws. Occlusal vertical dimension (OVD or VDO) or contact vertical dimension is the lower face height with the teeth in centric occlusion. Rest vertical dimension (VDR) is the lower face height measured from a chin point to a point just below the nose, with the mandible in rest position. (From Jablonski, Dictionary of Dentistry, 1992, p250)
The fibrous CONNECTIVE TISSUE surrounding the TOOTH ROOT, separating it from and attaching it to the alveolar bone (ALVEOLAR PROCESS).
A tooth from which the dental pulp has been removed or is necrotic. (Boucher, Clinical Dental Terminology, 4th ed)
Dens in Dente
Anomaly of the tooth, found chiefly in upper lateral incisors. It is characterized by invagination of the enamel at the incisal edge.
Dental Stress Analysis
Dental Enamel Hypoplasia
An acquired or hereditary condition due to deficiency in the formation of tooth enamel (AMELOGENESIS). It is usually characterized by defective, thin, or malformed DENTAL ENAMEL. Risk factors for enamel hypoplasia include gene mutations, nutritional deficiencies, diseases, and environmental factors.
The process whereby calcium salts are deposited in the dental enamel. The process is normal in the development of bones and teeth. (Boucher's Clinical Dental Terminology, 4th ed, p43)
The collective tissues from which an entire tooth is formed, including the DENTAL SAC; ENAMEL ORGAN; and DENTAL PAPILLA. (From Jablonski, Dictionary of Dentistry, 1992)
Small metal or ceramic attachments used to fasten an arch wire. These attachments are soldered or welded to an orthodontic band or cemented directly onto the teeth. Bowles brackets, edgewise brackets, multiphase brackets, ribbon arch brackets, twin-wire brackets, and universal brackets are all types of orthodontic brackets.
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)
Jaw Relation Record
A registration of any positional relationship of the mandible in reference to the maxillae. These records may be any of the many vertical, horizontal, or orientation relations. (Jablonski, Illustrated Dictionary of Dentistry)
Orthodontic Appliances, Removable
The selective extraction of deciduous teeth during the stage of mixed dentition in accordance with the shedding and eruption of the teeth. It is done over an extended period to allow autonomous adjustment to relieve crowding of the dental arches during the eruption of the lateral incisors, canines, and premolars, eventually involving the extraction of the first premolar teeth. (Dorland, 28th ed)
Dental Prosthesis Design
The plan and delineation of dental prostheses in general or a specific dental prosthesis. It does not include DENTURE DESIGN. The framework usually consists of metal.
The anatomical frontal portion of the mandible, also known as the mentum, that contains the line of fusion of the two separate halves of the mandible (symphysis menti). This line of fusion divides inferiorly to enclose a triangular area called the mental protuberance. On each side, inferior to the second premolar tooth, is the mental foramen for the passage of blood vessels and a nerve.
Dental procedure in which part of the pulp chamber is removed from the crown of a tooth.
A malocclusion in which maxillary incisor and canine teeth project over the mandiblar teeth excessively. The overlap is measured perpendicular to the occlusal plane and is also called vertical overlap. When the overlap is measured parallel to the occlusal plane it is referred to as overjet.
The force applied by the masticatory muscles in dental occlusion.
Dental Pulp Exposure
The result of pathological changes in the hard tissue of a tooth caused by carious lesions, mechanical factors, or trauma, which render the pulp susceptible to bacterial invasion from the external environment.
Orthodontic Anchorage Procedures
Orthodontic appliances, fixed or removable, used to maintain teeth in corrected positions during the period of functional adaptation following corrective treatment. These appliances are also used to maintain the positions of the teeth and jaws gained by orthodontic procedures. (From Zwemer, Boucher's Clinical Dental Terminology, 4th ed, p263)
An abnormal passage in the oral cavity on the gingiva.
Extraoral Traction Appliances
Extraoral devices for applying force to the dentition in order to avoid some of the problems in anchorage control met with in intermaxillary traction and to apply force in directions not otherwise possible.
The process of growth and differentiation of the jaws and face.
Dental Enamel Proteins
The proteins that are part of the dental enamel matrix.
Dental Implants, Single-Tooth
Devices, usually alloplastic, surgically inserted into or onto the jawbone, which support a single prosthetic tooth and serve either as abutments or as cosmetic replacements for missing teeth.
Root Canal Filling Materials
Materials placed inside a root canal for the purpose of obturating or sealing it. The materials may be gutta-percha, silver cones, paste mixtures, or other substances. (Dorland, 28th ed, p631 & Boucher's Clinical Dental Terminology, 4th ed, p187)
Dental cements composed either of polymethyl methacrylate or dimethacrylate, produced by mixing an acrylic monomer liquid with acrylic polymers and mineral fillers. The cement is insoluble in water and is thus resistant to fluids in the mouth, but is also irritating to the dental pulp. It is used chiefly as a luting agent for fabricated and temporary restorations. (Jablonski's Dictionary of Dentistry, 1992, p159)
The movement of teeth into altered positions in relationship to the basal bone of the ALVEOLAR PROCESS and to adjoining and opposing teeth as a result of loss of approximating or opposing teeth, occlusal interferences, habits, inflammatory and dystrophic disease of the attaching and supporting structures of the teeth. (From Boucher's Clinical Dental Terminology, 4th ed)
The facial skeleton, consisting of bones situated between the cranial base and the mandibular region. While some consider the facial bones to comprise the hyoid (HYOID BONE), palatine (HARD PALATE), and zygomatic (ZYGOMA) bones, MANDIBLE, and MAXILLA, others include also the lacrimal and nasal bones, inferior nasal concha, and vomer but exclude the hyoid bone. (Jablonski, Dictionary of Dentistry, 1992, p113)
Endodontic procedure performed to induce TOOTH APEX barrier development. ROOT CANAL FILLING MATERIALS are used to repair open apex or DENTAL PULP NECROSIS in an immature tooth. CALCIUM HYDROXIDE and mineral trioxide aggregate are commonly used as the filling materials.
An adhesion procedure for orthodontic attachments, such as plastic DENTAL CROWNS. This process usually includes the application of an adhesive material (DENTAL CEMENTS) and letting it harden in-place by light or chemical curing.
Root Canal Obturation
Devices used for influencing tooth position. Orthodontic appliances may be classified as fixed or removable, active or retaining, and intraoral or extraoral. (Boucher's Clinical Dental Terminology, 4th ed, p19)
Dental Restoration Failure
Loose-fitting removable orthodontic appliances which redirect the pressures of the facial and masticatory muscles onto the teeth and their supporting structures to produce improvements in tooth arrangements and occlusal relations.
The wearing away of a tooth as a result of tooth-to-tooth contact, as in mastication, occurring only on the occlusal, incisal, and proximal surfaces. It is chiefly associated with aging. It is differentiated from TOOTH ABRASION (the pathologic wearing away of the tooth substance by friction, as brushing, bruxism, clenching, and other mechanical causes) and from TOOTH EROSION (the loss of substance caused by chemical action without bacterial action). (Jablonski, Dictionary of Dentistry, 1992, p86)
Root Canal Preparation
Preparatory activities in ROOT CANAL THERAPY by partial or complete extirpation of diseased pulp, cleaning and sterilization of the empty canal, enlarging and shaping the canal to receive the sealing material. The cavity may be prepared by mechanical, sonic, chemical, or other means. (From Dorland, 28th ed, p1700)
Orthodontic Appliances, Functional
Loose, usually removable intra-oral devices which alter the muscle forces against the teeth and craniofacial skeleton. These are dynamic appliances which depend on altered neuromuscular action to effect bony growth and occlusal development. They are usually used in mixed dentition to treat pediatric malocclusions. (ADA, 1992)
Mechanical removal of a small amount of tooth structure (not more than a few tenths of a millimeter in depth) to eliminate superficial enamel discoloration defects not successfully removed by bleaching techniques. A common abrasive is a mixture of pumice and hydrochloric acid.
A hollow part of the alveolar process of the MAXILLA or MANDIBLE where each tooth fits and is attached via the periodontal ligament.
The formation of dentin. Dentin first appears in the layer between the ameloblasts and odontoblasts and becomes calcified immediately. Formation progresses from the tip of the papilla over its slope to form a calcified cap becoming thicker by the apposition of new layers pulpward. A layer of uncalcified dentin intervenes between the calcified tissue and the odontoblast and its processes. (From Jablonski, Dictionary of Dentistry, 1992)
The teeth collectively in the dental arch. Dentition ordinarily refers to the natural teeth in position in their alveoli. Dentition referring to the deciduous teeth is DENTITION, PRIMARY; to the permanent teeth, DENTITION, PERMANENT. (From Jablonski, Dictionary of Dentistry, 1992)
Dental Prosthesis Retention
Holding a DENTAL PROSTHESIS in place by its design, or by the use of additional devices or adhesives.
Dental Restoration, Permanent
Malocclusion, Angle Class III
Solid fixation of a tooth resulting from fusion of the cementum and alveolar bone, with obliteration of the periodontal ligament. It is uncommon in the deciduous dentition and very rare in permanent teeth. (Jablonski's Dictionary of Dentistry, 1992)
Denture, Partial, Fixed, Resin-Bonded
A commonly used prosthesis that results in a strong, permanent restoration. It consists of an electrolytically etched cast-metal retainer that is cemented (bonded), using resins, to adjacent teeth whose enamel was previously acid-treated (acid-etched). This type of bridgework is sometimes referred to as a Maryland bridge.
Substances used to bond COMPOSITE RESINS to DENTAL ENAMEL and DENTIN. These bonding or luting agents are used in restorative dentistry, ROOT CANAL THERAPY; PROSTHODONTICS; and ORTHODONTICS.
The intermediate sensory division of the trigeminal (5th cranial) nerve. The maxillary nerve carries general afferents from the intermediate region of the face including the lower eyelid, nose and upper lip, the maxillary teeth, and parts of the dura.
Dental Pulp Test
Investigations conducted on the physical health of teeth involving use of a tool that transmits hot or cold electric currents on a tooth's surface that can determine problems with that tooth based on reactions to the currents.
Diseases of the PERIAPICAL TISSUE surrounding the root of the tooth, which is distinguished from DENTAL PULP DISEASES inside the TOOTH ROOT.
The internal resistance of a material to moving some parts of it parallel to a fixed plane, in contrast to stretching (TENSILE STRENGTH) or compression (COMPRESSIVE STRENGTH). Ionic crystals are brittle because, when subjected to shear, ions of the same charge are brought next to each other, which causes repulsion.
Acid Etching, Dental
Preparation of TOOTH surfaces and DENTAL MATERIALS with etching agents, usually phosphoric acid, to roughen the surface to increase adhesion or osteointegration.
Physiologic loss of the primary dentition. (Zwemer, Boucher's Clinical Dental Terminology, 4th ed)
Tooth Preparation, Prosthodontic
The selected form given to a natural tooth when it is reduced by instrumentation to receive a prosthesis (e.g., artificial crown or a retainer for a fixed or removable prosthesis). The selection of the form is guided by clinical circumstances and physical properties of the materials that make up the prosthesis. (Boucher's Clinical Dental Terminology, 4th ed, p239)
A chronic endemic form of hypoplasia of the dental enamel caused by drinking water with a high fluorine content during the time of tooth formation, and characterized by defective calcification that gives a white chalky appearance to the enamel, which gradually undergoes brown discoloration. (Jablonski's Dictionary of Dentistry, 1992, p286)
A branch of the trigeminal (5th cranial) nerve. The mandibular nerve carries motor fibers to the muscles of mastication and sensory fibers to the teeth and gingivae, the face in the region of the mandible, and parts of the dura.
Root Canal Irrigants
Chemicals used mainly to disinfect root canals after pulpectomy and before obturation. The major ones are camphorated monochlorophenol, EDTA, formocresol, hydrogen peroxide, metacresylacetate, and sodium hypochlorite. Root canal irrigants include also rinsing solutions of distilled water, sodium chloride, etc.
A class of statistical methods applicable to a large set of probability distributions used to test for correlation, location, independence, etc. In most nonparametric statistical tests, the original scores or observations are replaced by another variable containing less information. An important class of nonparametric tests employs the ordinal properties of the data. Another class of tests uses information about whether an observation is above or below some fixed value such as the median, and a third class is based on the frequency of the occurrence of runs in the data. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1284; Corsini, Concise Encyclopedia of Psychology, 1987, p764-5)
The structures surrounding and supporting the tooth. Periodontium includes the gum (GINGIVA), the alveolar bone (ALVEOLAR PROCESS), the DENTAL CEMENTUM, and the PERIODONTAL LIGAMENT.
Alveolar Bone Loss
Resorption or wasting of the tooth-supporting bone (ALVEOLAR PROCESS) in the MAXILLA or MANDIBLE.
Denture, Complete, Upper
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)
A tooth's loss of minerals, such as calcium in hydroxyapatite from the tooth matrix, caused by acidic exposure. An example of the occurrence of demineralization is in the formation of dental caries.
The anterior portion of the head that includes the skin, muscles, and structures of the forehead, eyes, nose, mouth, cheeks, and jaw.
Exposure of the root surface when the edge of the gum (GINGIVA) moves apically away from the crown of the tooth. This is common with advancing age, vigorous tooth brushing, diseases, or tissue loss of the gingiva, the PERIODONTAL LIGAMENT and the supporting bone (ALVEOLAR PROCESS).
Any of several burrowing rodents of the families MURIDAE and Bathyergidae, found in eastern Europe, Africa, and Asia. They have short limbs, small eyes with permanently closed lids, and no tail. Three genera SPALAX (Muridae), Heterocephalus (Bathyergidae) and Cryptomys (Bathyergidae) are used frequently as experimental animals in biomedical research. (From Walker's Mammals of the World, 6th ed)
Radiography, Dental, Digital
A rapid, low-dose, digital imaging system using a small intraoral sensor instead of radiographic film, an intensifying screen, and a charge-coupled device. It presents the possibility of reduced patient exposure and minimal distortion, although resolution and latitude are inferior to standard dental radiography. A receiver is placed in the mouth, routing signals to a computer which images the signals on a screen or in print. It includes digitizing from x-ray film or any other detector. (From MEDLINE abstracts; personal communication from Dr. Charles Berthold, NIDR)
Dental Implantation, Endosseous, Endodontic
Insertion of a tapered rod through the root canal into the periapical osseous structure to lengthen the existing root and provide individual tooth stabilization.
Microscopy, Electron, Scanning
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.
Progressive loss of the hard substance of a tooth by chemical processes that do not involve bacterial action. (Jablonski, Dictionary of Dentistry, 1992, p296)
Cone-Beam Computed Tomography
Dental Implantation, Endosseous
A dental specialty concerned with the prevention and correction of dental and oral anomalies (malocclusion).
Polymeric resins derived from OXIRANES and characterized by strength and thermosetting properties. Epoxy resins are often used as dental materials.
Surgical excision of the gingiva at the level of its attachment, thus creating new marginal gingiva. This procedure is used to eliminate gingival or periodontal pockets or to provide an approach for extensive surgical interventions, and to gain access necessary to remove calculus within the pocket. (Dorland, 28th ed)
Finite Element Analysis
Zinc Oxide-Eugenol Cement
Inorganic derivatives of phosphoric acid (H3PO4). Note that organic derivatives of phosphoric acids are listed under ORGANOPHOSPHATES.
An artificial replacement for one or more natural teeth or part of a tooth, or associated structures, ranging from a portion of a tooth to a complete denture. The dental prosthesis is used for cosmetic or functional reasons, or both. DENTURES and specific types of dentures are also available. (From Boucher's Clinical Dental Terminology, 4th ed, p244 & Jablonski, Dictionary of Dentistry, 1992, p643)
Mesodermal tissue enclosed in the invaginated portion of the epithelial enamel organ and giving rise to the dentin and pulp.
Anterior midline brain, cranial, and facial malformations resulting from the failure of the embryonic prosencephalon to undergo segmentation and cleavage. Alobar prosencephaly is the most severe form and features anophthalmia; cyclopia; severe INTELLECTUAL DISABILITY; CLEFT LIP; CLEFT PALATE; SEIZURES; and microcephaly. Semilobar holoprosencepaly is characterized by hypotelorism, microphthalmia, coloboma, nasal malformations, and variable degrees of INTELLECTUAL DISABILITY. Lobar holoprosencephaly is associated with mild (or absent) facial malformations and intellectual abilities that range from mild INTELLECTUAL DISABILITY to normal. Holoprosencephaly is associated with CHROMOSOME ABNORMALITIES.
Denture, Partial, Fixed
Muscles arising in the zygomatic arch that close the jaw. Their nerve supply is masseteric from the mandibular division of the trigeminal nerve. (From Stedman, 25th ed)
PAX9 Transcription Factor
A paired box transcription factor that is involved in ODONTOGENESIS.
Subtotal or complete excision of the alveolar process of the maxilla or mandible. (Dorland, 28th ed)
Palatal Expansion Technique
A clinically and genetically heterogeneous group of hereditary conditions characterized by malformed DENTAL ENAMEL, usually involving DENTAL ENAMEL HYPOPLASIA and/or TOOTH HYPOMINERALIZATION.
Bisphenol A-Glycidyl Methacrylate
The use of a layer of tooth-colored material, usually porcelain or acrylic resin, applied to the surface of natural teeth, crowns, or pontics by fusion, cementation, or mechanical retention.
Techniques used for removal of bonded orthodontic appliances, restorations, or fixed dentures from teeth.