Methacrylates: Acrylic acids or acrylates which are substituted in the C-2 position with a methyl group.Polymethyl Methacrylate: 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.Methylmethacrylate: The methyl ester of methacrylic acid. It polymerizes easily to form POLYMETHYL METHACRYLATE. It is used as a bone cement.Polyhydroxyethyl Methacrylate: A biocompatible, hydrophilic, inert gel that is permeable to tissue fluids. It is used as an embedding medium for microscopy, as a coating for implants and prostheses, for contact lenses, as microspheres in adsorption research, etc.Methylmethacrylates: The methyl esters of methacrylic acid that polymerize easily and are used as tissue cements, dental materials, and absorbent for biological substances.Polymethacrylic Acids: Poly-2-methylpropenoic acids. Used in the manufacture of methacrylate resins and plastics in the form of pellets and granules, as absorbent for biological materials and as filters; also as biological membranes and as hydrogens. Synonyms: methylacrylate polymer; poly(methylacrylate); acrylic acid methyl ester polymer.Bisphenol A-Glycidyl Methacrylate: The reaction product of bisphenol A and glycidyl methacrylate that undergoes polymerization when exposed to ultraviolet light or mixed with a catalyst. It is used as a bond implant material and as the resin component of dental sealants and composite restorative materials.AcrylatesAcrylic ResinsMaterials Testing: The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.Dental Materials: Materials used in the production of dental bases, restorations, impressions, prostheses, etc.Polymerization: Chemical reaction in which monomeric components are combined to form POLYMERS (e.g., POLYMETHYLMETHACRYLATE).Denture Bases: The part of a denture that overlies the soft tissue and supports the supplied teeth and is supported in turn by abutment teeth or the residual alveolar ridge. It is usually made of resins or metal or their combination.Benzoyl Peroxide: A peroxide derivative that has been used topically for BURNS and as a dermatologic agent in the treatment of ACNE and POISON IVY DERMATITIS. It is used also as a bleach in the food industry.Polymers: Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).Wettability: The quality or state of being wettable or the degree to which something can be wet. This is also the ability of any solid surface to be wetted when in contact with a liquid whose surface tension is reduced so that the liquid spreads over the surface of the solid.Surface Properties: Characteristics or attributes of the outer boundaries of objects, including molecules.Nylons: Polymers where the main polymer chain comprises recurring amide groups. These compounds are generally formed from combinations of diamines, diacids, and amino acids and yield fibers, sheeting, or extruded forms used in textiles, gels, filters, sutures, contact lenses, and other biomaterials.Adhesives: Substances that cause the adherence of two surfaces. They include glues (properly collagen-derived adhesives), mucilages, sticky pastes, gums, resins, or latex.Composite Resins: Synthetic resins, containing an inert filler, that are widely used in dentistry.Resins, Synthetic: Polymers of high molecular weight which at some stage are capable of being molded and then harden to form useful components.Biocompatible Materials: Synthetic or natural materials, other than DRUGS, that are used to replace or repair any body TISSUES or bodily function.Siloxanes: Silicon polymers that contain alternate silicon and oxygen atoms in linear or cyclic molecular structures.Silanes: Compounds similar to hydrocarbons in which a tetravalent silicon atom replaces the carbon atom. They are very reactive, ignite in air, and form useful derivatives.Dental Cements: 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.Pliability: The quality or state of being able to be bent or creased repeatedly. (From Webster, 3d ed)Mechanical Phenomena: The properties and processes of materials that affect their behavior under force.Polyurethanes: A group of thermoplastic or thermosetting polymers containing polyisocyanate. They are used as ELASTOMERS, as coatings, as fibers and as foams.Tissue Embedding: The technique of placing cells or tissue in a supporting medium so that thin sections can be cut using a microtome. The medium can be paraffin wax (PARAFFIN EMBEDDING) or plastics (PLASTIC EMBEDDING) such as epoxy resins.Hydrogels: Water swollen, rigid, 3-dimensional network of cross-linked, hydrophilic macromolecules, 20-95% water. They are used in paints, printing inks, foodstuffs, pharmaceuticals, and cosmetics. (Grant & Hackh's Chemical Dictionary, 5th ed)Plastic Embedding: The infiltrating of histological specimens with plastics, including acrylic resins, epoxy resins and polyethylene glycol, for support of the tissues in preparation for sectioning with a microtome.Dentin-Bonding Agents: Cements that act through infiltration and polymerization within the dentinal matrix and are used for dental restoration. They can be adhesive resins themselves, adhesion-promoting monomers, or polymerization initiators that act in concert with other agents to form a dentin-bonding system.Dental Stress Analysis: The description and measurement of the various factors that produce physical stress upon dental restorations, prostheses, or appliances, materials associated with them, or the natural oral structures.Dental Technicians: Individuals responsible for fabrication of dental appliances.Dental Bonding: 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.Hardness: The mechanical property of material that determines its resistance to force. HARDNESS TESTS measure this property.Photoinitiators, Dental: Chemical compound used to initiate polymerization of dental resins by the use of DENTAL CURING LIGHTS. It absorbs UV light and undergoes decomposition into free radicals that initiate polymerization process of the resins in the mix. Each photoinitiator has optimum emission spectrum and intensity for proper curing of dental materials.Microchip Analytical Procedures: The preparation and analysis of samples on miniaturized devices.Dentin: 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)Resin Cements: 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)Dental Cavity Lining: An inner coating, as of varnish or other protective substance, to cover the dental cavity wall. It is usually a resinous film-forming agent dissolved in a volatile solvent, or a suspension of calcium hydroxide in a solution of a synthetic resin. The lining seals the dentinal tubules and protects the pulp before a restoration is inserted. (Jablonski, Illustrated Dictionary of Dentistry, 1982)Thermogravimetry: Technique whereby the weight of a sample can be followed over a period of time while its temperature is being changed (usually increased at a constant rate).Cycloparaffins: Alicyclic hydrocarbons in which three or more of the carbon atoms in each molecule are united in a ring structure and each of the ring carbon atoms is joined to two hydrogen atoms or alkyl groups. The simplest members are cyclopropane (C3H6), cyclobutane (C4H8), cyclohexane (C6H12), and derivatives of these such as methylcyclohexane (C6H11CH3). (From Sax, et al., Hawley's Condensed Chemical Dictionary, 11th ed)Compressive Strength: The maximum compression a material can withstand without failure. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p427)Denture Liners: Material applied to the tissue side of a denture to provide a soft lining to the parts of a denture coming in contact with soft tissue. It cushions contact of the denture with the tissues.Photoelectron Spectroscopy: The study of the energy of electrons ejected from matter by the photoelectric effect, i.e., as a direct result of absorption of energy from electromagnetic radiation. As the energies of the electrons are characteristic of a specific element, the measurement of the energy of these electrons is a technique used to determine the chemical composition of surfaces.Dental Restoration Wear: Occlusal wear of the surfaces of restorations and surface wear of dentures.PolyvinylsTensile Strength: The maximum stress a material subjected to a stretching load can withstand without tearing. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p2001)Elastic Modulus: Numerical expression indicating the measure of stiffness in a material. It is defined by the ratio of stress in a unit area of substance to the resulting deformation (strain). This allows the behavior of a material under load (such as bone) to be calculated.Hydrogel: A network of cross-linked hydrophilic macromolecules used in biomedical applications.Polystyrenes: Polymerized forms of styrene used as a biocompatible material, especially in dentistry. They are thermoplastic and are used as insulators, for injection molding and casting, as sheets, plates, rods, rigid forms and beads.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.Polyethylene Glycols: Polymers of ETHYLENE OXIDE and water, and their ethers. They vary in consistency from liquid to solid depending on the molecular weight indicated by a number following the name. They are used as SURFACTANTS, dispersing agents, solvents, ointment and suppository bases, vehicles, and tablet excipients. Some specific groups are NONOXYNOLS, OCTOXYNOLS, and POLOXAMERS.Acrylamides: Colorless, odorless crystals that are used extensively in research laboratories for the preparation of polyacrylamide gels for electrophoresis and in organic synthesis, and polymerization. Some of its polymers are used in sewage and wastewater treatment, permanent press fabrics, and as soil conditioning agents.Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Light-Curing of Dental Adhesives: The hardening or polymerization of bonding agents (DENTAL CEMENTS) via exposure to light.Fluorine Compounds: Inorganic compounds that contain fluorine as an integral part of the molecule.Fluorocarbon PolymersToluidinesAdsorption: The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.Dentin Solubility: The susceptibility of the DENTIN to dissolution.Glass: Hard, amorphous, brittle, inorganic, usually transparent, polymerous silicate of basic oxides, usually potassium or sodium. It is used in the form of hard sheets, vessels, tubing, fibers, ceramics, beads, etc.Differential Thermal Analysis: Technique by which phase transitions of chemical reactions can be followed by observation of the heat absorbed or liberated.Nanocomposites: Nanometer-scale composite structures composed of organic molecules intimately incorporated with inorganic molecules. (Glossary of Biotechnology and Nanobiotechology Terms, 4th ed)Tissue Conditioning (Dental): The use of a treatment material (tissue conditioner) to re-establish tone and health to irritated oral soft tissue, usually applied to the edentulous alveolar ridge.Dental Marginal Adaptation: The degree of approximation or fit of filling material or dental prosthetic to the tooth surface. A close marginal adaptation and seal at the interface is important for successful dental restorations.Deaf-Blind Disorders: The absence of both hearing and vision.Histological Techniques: Methods of preparing tissue for examination and study of the origin, structure, function, or pathology.Implants, Experimental: Artificial substitutes for body parts and materials inserted into organisms during experimental studies.Adhesiveness: A property of the surface of an object that makes it stick to another surface.Biofouling: Process by which unwanted microbial, plant or animal materials or organisms accumulate on man-made surfaces.Trimethyl Ammonium Compounds: QUATERNARY AMMONIUM COMPOUNDS containing three methyl groups, having the general formula of (CH3)3N+R.Microfluidic Analytical Techniques: Methods utilizing the principles of MICROFLUIDICS for sample handling, reagent mixing, and separation and detection of specific components in fluids.Bone Cements: 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.Streptococcus mitis: A species of gram-positive, coccoid bacteria commensal in the respiratory tract.Transition Temperature: The temperature at which a substance changes from one state or conformation of matter to another.Molecular Structure: The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.Histocytological Preparation Techniques: Methods of preparing cells or tissues for examination and study of their origin, structure, function, or pathology. The methods include preservation, fixation, sectioning, staining, replica, or other technique to allow for viewing using a microscope.Spectroscopy, Fourier Transform Infrared: A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.Silver: Silver. An element with the atomic symbol Ag, atomic number 47, and atomic weight 107.87. It is a soft metal that is used medically in surgical instruments, dental prostheses, and alloys. Long-continued use of silver salts can lead to a form of poisoning known as ARGYRIA.Lenses, Intraocular: Artificial implanted lenses.Gingiva: Oral tissue surrounding and attached to TEETH.Tissue Expansion Devices: Devices used to generate extra soft tissue in vivo to be used in surgical reconstructions. They exert stretching forces on the tissue and thus stimulate new growth and result in TISSUE EXPANSION. They are commonly inflatable reservoirs, usually made of silicone, which are implanted under the tissue and gradually inflated. Other tissue expanders exert stretching forces by attaching to outside of the body, for example, vacuum tissue expanders. Once the tissue has grown, the expander is removed and the expanded tissue is used to cover the area being reconstructed.Porosity: Condition of having pores or open spaces. This often refers to bones, bone implants, or bone cements, but can refer to the porous state of any solid substance.Tooth Preparation: Procedures carried out with regard to the teeth or tooth structures preparatory to specified dental therapeutic and surgical measures.Boron Compounds: Inorganic or organic compounds that contain boron as an integral part of the molecule.Saliva, Artificial: A solution used for irrigating the mouth in xerostomia and as a substitute for saliva.Polyesters: Polymers of organic acids and alcohols, with ester linkages--usually polyethylene terephthalate; can be cured into hard plastic, films or tapes, or fibers which can be woven into fabrics, meshes or velours.Prostheses and Implants: Artificial substitutes for body parts, and materials inserted into tissue for functional, cosmetic, or therapeutic purposes. Prostheses can be functional, as in the case of artificial arms and legs, or cosmetic, as in the case of an artificial eye. Implants, all surgically inserted or grafted into the body, tend to be used therapeutically. IMPLANTS, EXPERIMENTAL is available for those used experimentally.Tooth, Artificial: A fabricated tooth substituting for a natural tooth in a prosthesis. It is usually made of porcelain or plastic.Drug Carriers: Forms to which substances are incorporated to improve the delivery and the effectiveness of drugs. Drug carriers are used in drug-delivery systems such as the controlled-release technology to prolong in vivo drug actions, decrease drug metabolism, and reduce drug toxicity. Carriers are also used in designs to increase the effectiveness of drug delivery to the target sites of pharmacological actions. Liposomes, albumin microspheres, soluble synthetic polymers, DNA complexes, protein-drug conjugates, and carrier erythrocytes among others have been employed as biodegradable drug carriers.Calcium Phosphates: Calcium salts of phosphoric acid. These compounds are frequently used as calcium supplements.Dimethylpolysiloxanes: Silicone polymers which consist of silicon atoms substituted with methyl groups and linked by oxygen atoms. They comprise a series of biocompatible materials used as liquids, gels or solids; as film for artificial membranes, gels for implants, and liquids for drug vehicles; and as antifoaming agents.Microfluidics: The study of fluid channels and chambers of tiny dimensions of tens to hundreds of micrometers and volumes of nanoliters or picoliters. This is of interest in biological MICROCIRCULATION and used in MICROCHEMISTRY and INVESTIGATIVE TECHNIQUES.Antimutagenic Agents: Agents that reduce the frequency or rate of spontaneous or induced mutations independently of the mechanism involved.Dental Restoration, Permanent: A restoration designed to remain in service for not less than 20 to 30 years, usually made of gold casting, cohesive gold, or amalgam. (Jablonski, Dictionary of Dentistry, 1992)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.Microtechnology: Manufacturing technology for making microscopic devices in the micrometer range (typically 1-100 micrometers), such as integrated circuits or MEMS. The process usually involves replication and parallel fabrication of hundreds or millions of identical structures using various thin film deposition techniques and carried out in environmentally-controlled clean rooms.Gelatin: A product formed from skin, white connective tissue, or bone COLLAGEN. It is used as a protein food adjuvant, plasma substitute, hemostatic, suspending agent in pharmaceutical preparations, and in the manufacturing of capsules and suppositories.Nanoparticles: Nanometer-sized particles that are nanoscale in three dimensions. They include nanocrystaline materials; NANOCAPSULES; METAL NANOPARTICLES; DENDRIMERS, and QUANTUM DOTS. The uses of nanoparticles include DRUG DELIVERY SYSTEMS and cancer targeting and imaging.Quaternary Ammonium Compounds: Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.Coated Materials, Biocompatible: Biocompatible materials usually used in dental and bone implants that enhance biologic fixation, thereby increasing the bond strength between the coated material and bone, and minimize possible biological effects that may result from the implant itself.Denture Cleansers: Substances used to clean dentures; they are usually alkaline peroxides or hypochlorites, may contain enzymes and release oxygen. Use also for sonic action cleaners.Biomimetic Materials: Materials fabricated by BIOMIMETICS techniques, i.e., based on natural processes found in biological systems.Viscosity: The resistance that a gaseous or liquid system offers to flow when it is subjected to shear stress. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)para-Aminobenzoates: Benzoic acids, salts, or esters that contain an amino group attached to carbon number 4 of the benzene ring structure.Particle Size: Relating to the size of solids.Chitosan: Deacetylated CHITIN, a linear polysaccharide of deacetylated beta-1,4-D-glucosamine. It is used in HYDROGEL and to treat WOUNDS.Stainless Steel: Stainless steel. A steel containing Ni, Cr, or both. It does not tarnish on exposure and is used in corrosive environments. (Grant & Hack's Chemical Dictionary, 5th ed)Hydrophobic and Hydrophilic Interactions: The thermodynamic interaction between a substance and WATER.Dental Alloys: A mixture of metallic elements or compounds with other metallic or metalloid elements in varying proportions for use in restorative or prosthetic dentistry.Lens Capsule, Crystalline: The thin noncellular outer covering of the CRYSTALLINE LENS composed mainly of COLLAGEN TYPE IV and GLYCOSAMINOGLYCANS. It is secreted by the embryonic anterior and posterior epithelium. The embryonic posterior epithelium later disappears.Glutaral: One of the protein CROSS-LINKING REAGENTS that is used as a disinfectant for sterilization of heat-sensitive equipment and as a laboratory reagent, especially as a fixative.Equipment Design: Methods of creating machines and devices.Elasticity: Resistance and recovery from distortion of shape.Shear Strength: 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.Silicon Dioxide: Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.Aluminum Oxide: An oxide of aluminum, occurring in nature as various minerals such as bauxite, corundum, etc. It is used as an adsorbent, desiccating agent, and catalyst, and in the manufacture of dental cements and refractories.Tissue Scaffolds: Cell growth support structures composed of BIOCOMPATIBLE MATERIALS. They are specially designed solid support matrices for cell attachment in TISSUE ENGINEERING and GUIDED TISSUE REGENERATION uses.Nanofibers: Submicron-sized fibers with diameters typically between 50 and 500 nanometers. The very small dimension of these fibers can generate a high surface area to volume ratio, which makes them potential candidates for various biomedical and other applications.Absorption: The physical or physiological processes by which substances, tissue, cells, etc. take up or take in other substances or energy.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Equipment Failure Analysis: The evaluation of incidents involving the loss of function of a device. These evaluations are used for a variety of purposes such as to determine the failure rates, the causes of failures, costs of failures, and the reliability and maintainability of devices.Calorimetry, Differential Scanning: Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample.Solubility: The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Phase Transition: A change of a substance from one form or state to another.Biosensing Techniques: Any of a variety of procedures which use biomolecular probes to measure the presence or concentration of biological molecules, biological structures, microorganisms, etc., by translating a biochemical interaction at the probe surface into a quantifiable physical signal.Nanotechnology: The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.Titanium: 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)Tissue Engineering: Generating tissue in vitro for clinical applications, such as replacing wounded tissues or impaired organs. The use of TISSUE SCAFFOLDING enables the generation of complex multi-layered tissues and tissue structures.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Cell Survival: The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.Histocytochemistry: Study of intracellular distribution of chemicals, reaction sites, enzymes, etc., by means of staining reactions, radioactive isotope uptake, selective metal distribution in electron microscopy, or other methods.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.