Dental Impression Materials: Substances used to create an impression, or negative reproduction, of the teeth and dental arches. These materials include dental plasters and cements, metallic oxide pastes, silicone base materials, or elastomeric materials.Dental Impression Technique: Procedure of producing an imprint or negative likeness of the teeth and/or edentulous areas. Impressions are made in plastic material which becomes hardened or set while in contact with the tissue. They are later filled with plaster of Paris or artificial stone to produce a facsimile of the oral structures present. Impressions may be made of a full complement of teeth, of areas where some teeth have been removed, or in a mouth from which all teeth have been extracted. (Illustrated Dictionary of Dentistry, 1982)Resins, Synthetic: Polymers of high molecular weight which at some stage are capable of being molded and then harden to form useful components.Siloxanes: Silicon polymers that contain alternate silicon and oxygen atoms in linear or cyclic molecular structures.Silicone Elastomers: Polymers of silicone that are formed by crosslinking and treatment with amorphous silica to increase strength. They have properties similar to vulcanized natural rubber, in that they stretch under tension, retract rapidly, and fully recover to their original dimensions upon release. They are used in the encapsulation of surgical membranes and implants.PolyvinylsDental Disinfectants: Chemicals especially for use on instruments to destroy pathogenic organisms. (Boucher, Clinical Dental Terminology, 4th ed)Dental Models: Presentation devices used for patient education and technique training in dentistry.Dental Implants: Biocompatible materials placed into (endosseous) or onto (subperiosteal) the jawbone to support a crown, bridge, or artificial tooth, or to stabilize a diseased tooth.Education, Dental: Use for articles concerning dental education in general.Students, Dental: Individuals enrolled a school of dentistry or a formal educational program in leading to a degree in dentistry.Dental Care: The total of dental diagnostic, preventive, and restorative services provided to meet the needs of a patient (from Illustrated Dictionary of Dentistry, 1982).Silicones: A broad family of synthetic organosiloxane polymers containing a repeating silicon-oxygen backbone with organic side groups attached via carbon-silicon bonds. Depending on their structure, they are classified as liquids, gels, and elastomers. (From Merck Index, 12th ed)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)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.Prescription Drug Misuse: Improper use of drugs or medications outside the intended purpose, scope, or guidelines for use. This is in contrast to MEDICATION ADHERENCE, and distinguished from DRUG ABUSE, which is a deliberate or willful action.Alginates: Salts of alginic acid that are extracted from marine kelp and used to make dental impressions and as absorbent material for surgical dressings.Schools, Dental: Educational institutions for individuals specializing in the field of dentistry.Silicone Oils: Organic siloxanes which are polymerized to the oily stage. The oils have low surface tension and density less than 1. They are used in industrial applications and in the treatment of retinal detachment, complicated by proliferative vitreoretinopathy.American Dental Association: Professional society representing the field of dentistry.Medical Laboratory Personnel: Health care professionals, technicians, and assistants staffing LABORATORIES in research or health care facilities.Dental Technicians: Individuals responsible for fabrication of dental appliances.Laboratory Personnel: Professionals, technicians, and assistants staffing LABORATORIES.Endodontics: A dental specialty concerned with the maintenance of the dental pulp in a state of health and the treatment of the pulp cavity (pulp chamber and pulp canal).Vinyl CompoundsVinyl Chloride: A gas that has been used as an aerosol propellant and is the starting material for polyvinyl resins. Toxicity studies have shown various adverse effects, particularly the occurrence of liver neoplasms.Prosthodontics: A dental specialty concerned with the restoration and maintenance of oral function by the replacement of missing TEETH and related structures by artificial devices or DENTAL PROSTHESES.Dental Equipment: The nonexpendable items used by the dentist or dental staff in the performance of professional duties. (From Boucher's Clinical Dental Terminology, 4th ed, p106)Counterfeit Drugs: Drugs manufactured and sold with the intent to misrepresent its origin, authenticity, chemical composition, and or efficacy. Counterfeit drugs may contain inappropriate quantities of ingredients not listed on the label or package. In order to further deceive the consumer, the packaging, container, or labeling, may be inaccurate, incorrect, or fake.Oral Medicine: A branch of dentistry dealing with diseases of the oral and paraoral structures and the oral management of systemic diseases. (Hall, What is Oral Medicine, Anyway? Clinical Update: National Naval Dental Center, March 1991, p7-8)Introversion (Psychology): A state in which attention is largely directed inward upon one's self.Fraud: Exploitation through misrepresentation of the facts or concealment of the purposes of the exploiter.Gingival Retraction Techniques: Techniques used to expose dental surface below the gingival margin in order to obtain better dental impression during periodental and peri-implant applications. The retraction of the gingival tissue can be achieved surgically (e.g., laser gingivectomy and rotary curettage) or chemically with a retraction cord.Saliva: The clear, viscous fluid secreted by the SALIVARY GLANDS and mucous glands of the mouth. It contains MUCINS, water, organic salts, and ptylin.EthersSterilization: The destroying of all forms of life, especially microorganisms, by heat, chemical, or other means.Patents as Topic: Exclusive legal rights or privileges applied to inventions, plants, etc.Elastomers: A generic term for all substances having the properties of stretching under tension, high tensile strength, retracting rapidly, and recovering their original dimensions fully. They are generally POLYMERS.Electronics: The study, control, and application of the conduction of ELECTRICITY through gases or vacuum, or through semiconducting or conducting materials. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Electronics, Medical: The research and development of ELECTRICAL EQUIPMENT AND SUPPLIES for such medical applications as diagnosis, therapy, research, anesthesia control, cardiac control, and surgery. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Pit and Fissure Sealants: Agents used to occlude dental enamel pits and fissures in the prevention of dental caries.Composite Resins: Synthetic resins, containing an inert filler, that are widely used in dentistry.Polymerization: Chemical reaction in which monomeric components are combined to form POLYMERS (e.g., POLYMETHYLMETHACRYLATE).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.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)China: A country spanning from central Asia to the Pacific Ocean.Syringes: Instruments used for injecting or withdrawing fluids. (Stedman, 25th ed)Needle-Exchange Programs: Organized services for exchange of sterile needles and syringes used for injections as a potential means of reducing the transmission of infectious diseases.Substance Abuse, Intravenous: Abuse, overuse, or misuse of a substance by its injection into a vein.Injections, Jet: The injection of solutions into the skin by compressed air devices so that only the solution pierces the skin.Equipment Design: Methods of creating machines and devices.Needles: Sharp instruments used for puncturing or suturing.