Gold Alloys: Alloys that contain a high percentage of gold. They are used in restorative or prosthetic dentistry.Alloys: A mixture of metallic elements or compounds with other metallic or metalloid elements in varying proportions.Chromium Alloys: Specific alloys not less than 85% chromium and nickel or cobalt, with traces of either nickel or cobalt, molybdenum, and other substances. They are used in partial dentures, orthopedic implants, etc.Gold: A yellow metallic element with the atomic symbol Au, atomic number 79, and atomic weight 197. It is used in jewelry, goldplating of other metals, as currency, and in dental restoration. Many of its clinical applications, such as ANTIRHEUMATIC AGENTS, are in the form of its salts.Dental Casting Technique: The process of producing a form or impression made of metal or plaster using a mold.Thiouracil: Occurs in seeds of Brassica and Crucifera species. Thiouracil has been used as antithyroid, coronary vasodilator, and in congestive heart failure although its use has been largely supplanted by other drugs. It is known to cause blood dyscrasias and suspected of terato- and carcinogenesis.Materials 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 Polishing: Creation of a smooth and glossy surface finish on a denture or amalgam.Dental Casting Investment: Material from which the casting mold is made in the fabrication of gold or cobalt-chromium castings. (Boucher's Clinical Dental Terminology, 4th ed, p168)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.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.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)ThionesElectron 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.Methylmethacrylates: The methyl esters of methacrylic acid that polymerize easily and are used as tissue cements, dental materials, and absorbent for biological substances.Denture Retention: The retention of a denture in place by design, device, or adhesion.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 Alloys: A mixture of metallic elements or compounds with other metallic or metalloid elements in varying proportions for use in restorative or prosthetic dentistry.Methacrylates: Acrylic acids or acrylates which are substituted in the C-2 position with a methyl group.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.Crowns: A prosthetic restoration that reproduces the entire surface anatomy of the visible natural crown of a tooth. It may be partial (covering three or more surfaces of a tooth) or complete (covering all surfaces). It is made of gold or other metal, porcelain, or resin.Surface Properties: Characteristics or attributes of the outer boundaries of objects, including molecules.Denture, Overlay: Removable prosthesis constructed over natural teeth or implanted studs.Corrosion: The gradual destruction of a metal or alloy due to oxidation or action of a chemical agent. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)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.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.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 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.Dental Prosthesis Retention: Holding a DENTAL PROSTHESIS in place by its design, or by the use of additional devices or adhesives.Dental Clasps: Metal devices for fastening together two or more parts of dental prostheses for stabilizing or retaining them by attachment to abutment teeth. For a precision attachment for a partial denture DENTURE PRECISION ATTACHMENT is available.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 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.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.Boron Compounds: Inorganic or organic compounds that contain boron as an integral part of the molecule.Dental Materials: Materials used in the production of dental bases, restorations, impressions, prostheses, etc.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.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.Composite Resins: Synthetic resins, containing an inert filler, that are widely used in dentistry.Tin: A trace element that is required in bone formation. It has the atomic symbol Sn, atomic number 50, and atomic weight 118.71.Oxides: Binary compounds of oxygen containing the anion O(2-). The anion combines with metals to form alkaline oxides and non-metals to form acidic oxides.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.Gold Sodium Thiomalate: A variable mixture of the mono- and disodium salts of gold thiomalic acid used mainly for its anti-inflammatory action in the treatment of rheumatoid arthritis. It is most effective in active progressive rheumatoid arthritis and of little or no value in the presence of extensive deformities or in the treatment of other forms of arthritis.Gold Compounds: Inorganic compounds that contain gold as an integral part of the molecule.Stress, Mechanical: 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.Differential Thermal Analysis: Technique by which phase transitions of chemical reactions can be followed by observation of the heat absorbed or liberated.Metal Nanoparticles: Nanoparticles produced from metals whose uses include biosensors, optics, and catalysts. In biomedical applications the particles frequently involve the noble metals, especially gold and silver.Nickel: A trace element with the atomic symbol Ni, atomic number 28, and atomic weight 58.69. It is a cofactor of the enzyme UREASE.Hardness: The mechanical property of material that determines its resistance to force. HARDNESS TESTS measure this property.Gallium: A rare, metallic element designated by the symbol, Ga, atomic number 31, and atomic weight 69.72.Niobium: Niobium. A metal element atomic number 41, atomic weight 92.906, symbol Nb. (From Dorland, 28th ed)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)Tensile 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)Electroplating: Coating with a metal or alloy by electrolysis.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)Indium: A metallic element, atomic number 49, atomic weight 114.82, symbol In. It is named from its blue line in the spectrum. (From Dorland, 28th ed)