Polyurethanes: A group of thermoplastic or thermosetting polymers containing polyisocyanate. They are used as ELASTOMERS, as coatings, as fibers and as foams.Isocyanates: Organic compounds that contain the -NCO radical.Toluene 2,4-Diisocyanate: Skin irritant and allergen used in the manufacture of polyurethane foams and other elastomers.Castor Oil: Oil obtained from seeds of Ricinus communis that is used as a cathartic and as a plasticizer.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)Cyanates: Organic salts of cyanic acid containing the -OCN radical.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.Biocompatible Materials: Synthetic or natural materials, other than DRUGS, that are used to replace or repair any body TISSUES or bodily function.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.Implants, Experimental: Artificial substitutes for body parts and materials inserted into organisms during experimental studies.Polyvinyl Chloride: A polyvinyl resin used extensively in the manufacture of plastics, including medical devices, tubing, and other packaging. It is also used as a rubber substitute.Equipment Failure: Failure of equipment to perform to standard. The failure may be due to defects or improper use.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.Chemical Industry: The aggregate enterprise of manufacturing and technically producing chemicals. (From Random House Unabridged Dictionary, 2d ed)Air Pollutants, Occupational: Air pollutants found in the work area. They are usually produced by the specific nature of the occupation.Adhesives: Substances that cause the adherence of two surfaces. They include glues (properly collagen-derived adhesives), mucilages, sticky pastes, gums, resins, or latex.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.Gastrostomy: Creation of an artificial external opening into the stomach for nutritional support or gastrointestinal compression.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.Surface Properties: Characteristics or attributes of the outer boundaries of objects, including molecules.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.Scleral Diseases: General disorders of the sclera or white of the eye. They may include anatomic, embryologic, degenerative, or pigmentation defects.Catheters, Indwelling: Catheters designed to be left within an organ or passage for an extended period of time.Latex: A milky, product excreted from the latex canals of a variety of plant species that contain cauotchouc. Latex is composed of 25-35% caoutchouc, 60-75% water, 2% protein, 2% resin, 1.5% sugar & 1% ash. RUBBER is made by the removal of water from latex.(From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed). Hevein proteins are responsible for LATEX HYPERSENSITIVITY. Latexes are used as inert vehicles to carry antibodies or antigens in LATEX FIXATION TESTS.Electroplating: Coating with a metal or alloy by electrolysis.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.Occlusive Dressings: Material, usually gauze or absorbent cotton, used to cover and protect wounds, to seal them from contact with air or bacteria. (From Dorland, 27th ed)Zygoma: Either of a pair of bones that form the prominent part of the CHEEK and contribute to the ORBIT on each side of the SKULL.Foreign-Body Reaction: Chronic inflammation and granuloma formation around irritating foreign bodies.