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.
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.
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.
The growth action of bone tissue as it assimilates surgically implanted devices or prostheses to be used as either replacement parts (e.g., hip) or as anchors (e.g., endosseous dental implants).
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 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.
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.
Characteristics or attributes of the outer boundaries of objects, including molecules.
The amount of force generated by MUSCLE CONTRACTION. Muscle strength can be measured during isometric, isotonic, or isokinetic contraction, either manually or using a device such as a MUSCLE STRENGTH DYNAMOMETER.
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)
Force exerted when gripping or grasping.
The maximum compression a material can withstand without failure. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p427)
The deformation and flow behavior of BLOOD and its elements i.e., PLASMA; ERYTHROCYTES; WHITE BLOOD CELLS; and BLOOD PLATELETS.
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)
A device that measures MUSCLE STRENGTH during muscle contraction, such as gripping, pushing, and pulling. It is used to evaluate the health status of muscle in sports medicine or physical therapy.
Substances that cause the adherence of two surfaces. They include glues (properly collagen-derived adhesives), mucilages, sticky pastes, gums, resins, or latex.
A family of gram-positive bacteria in the order Lactobacillales. Lactic acid is the main product of their carbohydrate metabolism.
A flavonol glycoside found in many plants, including BUCKWHEAT; TOBACCO; FORSYTHIA; HYDRANGEA; VIOLA, etc. It has been used therapeutically to decrease capillary fragility.
Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.
Proteins found in any species of bacterium.
Argon. A noble gas with the atomic symbol Ar, atomic number 18, and atomic weight 39.948. It is used in fluorescent tubes and wherever an inert atmosphere is desired and nitrogen cannot be used.
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.
The use of photothermal effects of LASERS to coagulate, incise, vaporize, resect, dissect, or resurface tissue.
A United States organization of distinguished scientists and engineers established for the purpose of investigating and reporting upon any subject of art or science as requested by any department of government. The National Research Council organized by NAS serves as the principal operating agency to stimulate and support research.
A colloidal, hydrated aluminum silicate that swells 12 times its dry size when added to water.
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.
Detailed account or statement or formal record of data resulting from empirical inquiry.
Identifies, for study and analysis, important issues and problems that relate to health and medicine. The Institute initiates and conducts studies of national policy and planning for health care and health-related education and research; it also responds to requests from the federal government and other agencies for studies and advice.
Treatment modality for DENTAL CARIES that uses manual excavation method and GLASS IONOMER CEMENTS. Because of its noninvasiveness and no need for expensive equipment and anesthesia it is promoted as an approach in places where dental care is not readily available.
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.
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)
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)
Nanometer-sized tubes composed mainly of CARBON. Such nanotubes are used as probes for high-resolution structural and chemical imaging of biomolecules with ATOMIC FORCE MICROSCOPY.
Materials which have structured components with at least one dimension in the range of 1 to 100 nanometers. These include NANOCOMPOSITES; NANOPARTICLES; NANOTUBES; and NANOWIRES.
Nanometer-sized tubes composed of various substances including carbon (CARBON NANOTUBES), boron nitride, or nickel vanadate.
The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.
Individual's rights to obtain and use information collected or generated by others.
Nanometer-scale composite structures composed of organic molecules intimately incorporated with inorganic molecules. (Glossary of Biotechnology and Nanobiotechology Terms, 4th ed)
Preparation of TOOTH surfaces and DENTAL MATERIALS with etching agents, usually phosphoric acid, to roughen the surface to increase adhesion or osteointegration.
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.
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.
Devices or pieces of equipment placed in or around the mouth or attached to instruments to protect the external or internal tissues of the mouth and the teeth.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)