Materials Testing
Dental Materials
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.
Methacrylates
Dental Restoration, Permanent
Resins, Synthetic
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.
Resins, Plant
Flammable, amorphous, vegetable products of secretion or disintegration, usually formed in special cavities of plants. They are generally insoluble in water and soluble in alcohol, carbon tetrachloride, ether, or volatile oils. They are fusible and have a conchoidal fracture. They are the oxidation or polymerization products of the terpenes, and are mixtures of aromatic acids and esters. Most are soft and sticky, but harden after exposure to cold. (From Grant & Hackh's Chemical Dictionary, 5th ed & Dorland, 28th ed)
Hardness
The mechanical property of material that determines its resistance to force. HARDNESS TESTS measure this property.
Dental Stress Analysis
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.
Light-Curing of Dental Adhesives
Curing Lights, Dental
Light sources used to activate polymerization of light-cured DENTAL CEMENTS and DENTAL RESINS. Degree of cure and bond strength depends on exposure time, wavelength, and intensity of the curing light.
Surface Properties
Polyurethanes
A group of thermoplastic or thermosetting polymers containing polyisocyanate. They are used as ELASTOMERS, as coatings, as fibers and as foams.
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)
Nanocomposites
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.
Crowns
Dental Restoration Failure
Zirconium
Pliability
Dental Cavity Preparation
An operation in which carious material is removed from teeth and biomechanically correct forms are established in the teeth to receive and retain restorations. A constant requirement is provision for prevention of failure of the restoration through recurrence of decay or inadequate resistance to applied stresses. (Boucher's Clinical Dental Terminology, 4th ed, p239-40)
Compomers
Composite materials composed of an ion-leachable glass embedded in a polymeric matrix. They differ from GLASS IONOMER CEMENTS in that partially silanized glass particles are used to provide a direct bond to the resin matrix and the matrix is primarily formed by a light-activated, radical polymerization reaction.
Polymerization
Chemical reaction in which monomeric components are combined to form POLYMERS (e.g., POLYMETHYLMETHACRYLATE).
Self-Curing of Dental Resins
The hardening or polymerization of bonding agents (DENTAL CEMENTS) via chemical reactions, usually involving two components. This type of dental bonding uses a self-cure or dual-cure system.
Tensile Strength
Dental Enamel
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)
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 Marginal Adaptation
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.
Dentin
Glass Ionomer Cements
A polymer obtained by reacting polyacrylic acid with a special anion-leachable glass (alumino-silicate). The resulting cement is more durable and tougher than others in that the materials comprising the polymer backbone do not leach out.
Post and Core Technique
Saliva, Artificial
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.
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.
Siloxanes
Phosphoric Acids
Inorganic derivatives of phosphoric acid (H3PO4). Note that organic derivatives of phosphoric acids are listed under ORGANOPHOSPHATES.
Ion Exchange Resins
High molecular weight, insoluble polymers which contain functional groups that are capable of undergoing exchange reactions (ION EXCHANGE) with either cations or anions.
Inlays
Silorane Resins
Polymeric resins containing a combination of SILOXANES and OXIRANES.
Color
The visually perceived property of objects created by absorption or reflection of specific wavelengths of light.
Dental Restoration Repair
Tooth Fractures
Break or rupture of a tooth or tooth root.
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.
Dental Etching
Preparation of TOOTH surfaces, and of materials bonded to teeth or DENTAL IMPLANTS, with agents and methods which roughen the surface to facilitate adhesion. Agents include phosphoric or other acids (ACID ETCHING, DENTAL) and methods include LASERS.
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)
Gold Alloys
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.
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.
Epoxy Resins
Polymeric resins derived from OXIRANES and characterized by strength and thermosetting properties. Epoxy resins are often used as dental materials.
Tooth, Nonvital
A tooth from which the dental pulp has been removed or is necrotic. (Boucher, Clinical Dental Terminology, 4th ed)
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.
Carbon Compounds, Inorganic
Hardness Tests
A test to determine the relative hardness of a metal, mineral, or other material according to one of several scales, such as Brinell, Mohs, Rockwell, Vickers, or Shore. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Physicochemical Processes
Dental Porcelain
A type of porcelain used in dental restorations, either jacket crowns or inlays, artificial teeth, or metal-ceramic crowns. It is essentially a mixture of particles of feldspar and quartz, the feldspar melting first and providing a glass matrix for the quartz. Dental porcelain is produced by mixing ceramic powder (a mixture of quartz, kaolin, pigments, opacifiers, a suitable flux, and other substances) with distilled water. (From Jablonski's Dictionary of Dentistry, 1992)
Tooth, Artificial
Tooth Bleaching Agents
Dental Leakage
Ceramics
Toothbrushing
Bicuspid
Stress, Mechanical
Dental Restoration, Temporary
A prosthesis or restoration placed for a limited period, from several days to several months, which is designed to seal the tooth and maintain its position until a permanent restoration (DENTAL RESTORATION, PERMANENT) will replace it. (From Jablonski, Dictionary of Dentistry, 1992)
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.
Dental Veneers
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.
Aluminum Silicates
Any of the numerous types of clay which contain varying proportions of Al2O3 and SiO2. They are made synthetically by heating aluminum fluoride at 1000-2000 degrees C with silica and water vapor. (From Hawley's Condensed Chemical Dictionary, 11th ed)
Dental Alloys
Organically Modified Ceramics
Tooth Abrasion
The pathologic wearing away of the tooth substance by brushing, bruxism, clenching, and other mechanical causes. It is differentiated from TOOTH ATTRITION in that this type of wearing away is the result of tooth-to-tooth contact, as in mastication, occurring only on the occlusal, incisal, and proximal surfaces. It differs also from TOOTH EROSION, the progressive loss of the hard substance of a tooth by chemical processes not involving bacterial action. (From Jablonski, Dictionary of Dentistry, 1992, p2)
Analysis of Variance
Electron Probe Microanalysis
Identification and measurement of ELEMENTS and their location based on the fact that X-RAYS emitted by an element excited by an electron beam have a wavelength characteristic of that element and an intensity related to its concentration. It is performed with an electron microscope fitted with an x-ray spectrometer, in scanning or transmission mode.
Tooth Bleaching
The use of a chemical oxidizing agent to whiten TEETH. In some procedures the oxidation process is activated by the use of heat or light.
Dental Amalgam
An alloy used in restorative dentistry that contains mercury, silver, tin, copper, and possibly zinc.
Stainless Steel
Halogens
Diamond
Diamond. A crystalline form of carbon that occurs as hard, colorless or tinted isomeric crystals. It is used as a precious stone, for cutting glass, and as bearings for delicate mechanisms. (From Grant & Hackh's Chemical Dictionary, 5th ed)
Water
Dental Abutments
Silicates
The generic term for salts derived from silica or the silicic acids. They contain silicon, oxygen, and one or more metals, and may contain hydrogen. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th Ed)
Adhesives
Substances that cause the adherence of two surfaces. They include glues (properly collagen-derived adhesives), mucilages, sticky pastes, gums, resins, or latex.
Orthodontic Brackets
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.
Molar
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)
Tooth Preparation
Silicon Compounds
Inorganic compounds that contain silicon as an integral part of the molecule.
Polycarboxylate Cement
Water-soluble low-molecular-weight polymers of acrylic or methacrylic acid that form solid, insoluble products when mixed with specially prepared ZnO powder. The resulting cement adheres to dental enamel and is also used as a luting agent.
Tooth Root
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)
Quartz
Quartz (SiO2). A glassy or crystalline form of silicon dioxide. Many colored varieties are semiprecious stones. (From Grant & Hackh's Chemical Dictionary, 5th 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)
Methylmethacrylates
The methyl esters of methacrylic acid that polymerize easily and are used as tissue cements, dental materials, and absorbent for biological substances.
Compressive Strength
Anion Exchange Resins
High-molecular-weight insoluble polymers that contain functional cationic groups capable of undergoing exchange reactions with anions.
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.
Wettability
Hydrofluoric Acid
Hydrofluoric acid. A solution of hydrogen fluoride in water. It is a colorless fuming liquid which can cause painful burns.
Denture, Partial
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).
Colorimetry
Any technique by which an unknown color is evaluated in terms of standard colors. The technique may be visual, photoelectric, or indirect by means of spectrophotometry. It is used in chemistry and physics. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Cariostatic Agents
Substances that inhibit or arrest DENTAL CARIES formation. (Boucher's Clinical Dental Terminology, 4th ed)
Polymers
Elastic Modulus
Cation Exchange Resins
High molecular weight insoluble polymers which contain functional anionic groups that are capable of undergoing exchange reactions with cations.
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.
Tooth Cervix
Dental Equipment
Denture Bases
Statistics, Nonparametric
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)
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.
Air Abrasion, Dental
A technique using a pneumatic, high-pressure stream of aluminum oxide to remove DENTAL ENAMEL; DENTIN; and restorative materials from teeth. In contrast to using DENTAL HIGH-SPEED EQUIPMENT, this method usually requires no dental anesthesia (ANESTHESIA, DENTAL) and reduces risks of tooth chipping and microfracturing. It is used primarily for routine DENTAL CAVITY PREPARATION.
Semiconductors
Photochemical Processes
Chemical reactions effected by light.
Magnesium Oxide
Magnesium oxide (MgO). An inorganic compound that occurs in nature as the mineral periclase. In aqueous media combines quickly with water to form magnesium hydroxide. It is used as an antacid and mild laxative and has many nonmedicinal uses.
Incisor
Methylmethacrylate
The methyl ester of methacrylic acid. It polymerizes easily to form POLYMETHYL METHACRYLATE. It is used as a bone cement.
Tooth, Deciduous
Pseudoephedrine
Astringents
Dentistry, Operative
That phase of clinical dentistry concerned with the restoration of parts of existing teeth that are defective through disease, trauma, or abnormal development, to the state of normal function, health, and esthetics, including preventive, diagnostic, biological, mechanical, and therapeutic techniques, as well as material and instrument science and application. (Jablonski's Dictionary of Dentistry, 2d ed, p237)
Dental Prosthesis Repair
Metal Ceramic Alloys
The fusion of ceramics (porcelain) to an alloy of two or more metals for use in restorative and prosthodontic dentistry. Examples of metal alloys employed include cobalt-chromium, gold-palladium, gold-platinum-palladium, and nickel-based alloys.
Temperature
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
Esthetics, Dental
Spectrometry, X-Ray Emission
The spectrometric analysis of fluorescent X-RAYS, i.e. X-rays emitted after bombarding matter with high energy particles such as PROTONS; ELECTRONS; or higher energy X-rays. Identification of ELEMENTS by this technique is based on the specific type of X-rays that are emitted which are characteristic of the specific elements in the material being analyzed. The characteristic X-rays are distinguished and/or quantified by either wavelength dispersive or energy dispersive methods.
Zinc Oxide
A mild astringent and topical protectant with some antiseptic action. It is also used in bandages, pastes, ointments, dental cements, and as a sunblock.
Absorption
Tooth Demineralization
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.
Titanium
Fluorides
Inorganic salts of hydrofluoric acid, HF, in which the fluorine atom is in the -1 oxidation state. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed) Sodium and stannous salts are commonly used in dentifrices.
Optical Phenomena
Dental Caries
Localized destruction of the tooth surface initiated by decalcification of the enamel followed by enzymatic lysis of organic structures and leading to cavity formation. If left unchecked, the cavity may penetrate the enamel and dentin and reach the pulp.
Cuspid
Dental Pulp Capping
Application of a protective agent to an exposed pulp (direct capping) or the remaining thin layer of dentin over a nearly exposed pulp (indirect capping) in order to allow the pulp to recover and maintain its normal vitality and function.
Coloring Agents
Chemicals and substances that impart color including soluble dyes and insoluble pigments. They are used in INKS; PAINTS; and as INDICATORS AND REAGENTS.
Mouthwashes
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.
Erbium
Food Coloring Agents
Natural or synthetic dyes used as coloring agents in processed foods.
Tooth Crown
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)
Cementation
The joining of objects by means of a cement (e.g., in fracture fixation, such as in hip arthroplasty for joining of the acetabular component to the femoral component). In dentistry, it is used for the process of attaching parts of a tooth or restorative material to a natural tooth or for the attaching of orthodontic bands to teeth by means of an adhesive.
Finite Element Analysis
Spectroscopy, Fourier Transform Infrared
Coffee
A beverage made from ground COFFEA beans (SEEDS) infused in hot water. It generally contains CAFFEINE and THEOPHYLLINE unless it is decaffeinated.
Streptococcus oralis
Rubber
A high-molecular-weight polymeric elastomer derived from the milk juice (LATEX) of HEVEA brasiliensis and other trees and plants. It is a substance that can be stretched at room temperature to at least twice its original length and after releasing the stress, retract rapidly, and recover its original dimensions fully.
Viscosity
Palladium
A chemical element having an atomic weight of 106.4, atomic number of 46, and the symbol Pd. It is a white, ductile metal resembling platinum, and following it in abundance and importance of applications. It is used in dentistry in the form of gold, silver, and copper alloys.
Streptococcus sobrinus
A species of gram-positive, coccoid bacteria isolated from the human tooth surface. Strains have been shown to be cariogenic in experimental animals and may be associated with human dental caries.
Random Allocation
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)
Peroxides
A group of compounds that contain a bivalent O-O group, i.e., the oxygen atoms are univalent. They can either be inorganic or organic in nature. Such compounds release atomic (nascent) oxygen readily. Thus they are strong oxidizing agents and fire hazards when in contact with combustible materials, especially under high-temperature conditions. The chief industrial uses of peroxides are as oxidizing agents, bleaching agents, and initiators of polymerization. (From Hawley's Condensed Chemical Dictionary, 11th ed)
Dental Pulp
A richly vascularized and innervated connective tissue of mesodermal origin, contained in the central cavity of a tooth and delimited by the dentin, and having formative, nutritive, sensory, and protective functions. (Jablonski, Dictionary of Dentistry, 1992)
Dental Occlusion, Traumatic
Boron Compounds
Denture Design
Air Pressure
The force per unit area that the air exerts on any surface in contact with it. Primarily used for articles pertaining to air pressure within a closed environment.
Friction
Cattle
Hot Temperature
Presence of warmth or heat or a temperature notably higher than an accustomed norm.
Porosity
Silicon
A trace element that constitutes about 27.6% of the earth's crust in the form of SILICON DIOXIDE. It does not occur free in nature. Silicon has the atomic symbol Si, atomic number 14, and atomic weight [28.084; 28.086].
Calcium Phosphates
Pit and Fissure Sealants
Glutaral
Methylcellulose
Methylester of cellulose. Methylcellulose is used as an emulsifying and suspending agent in cosmetics, pharmaceutics and the chemical industry. It is used therapeutically as a bulk laxative.
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.