This article focuses on the use of noble and precious metals for biomedical applications. These include gold, platinum, palladium, ruthenium, rhodium, iridium, and osmium. The physical and mechanical properties of noble and precious metals are presented in tables. A brief discussion on the ancient history of noble and precious metal use in dentistry is provided. The article discusses the use of direct gold dental filling materials, direct silver dental filling materials, traditional amalgam alloys, high-copper amalgam alloys, and gallium alloys in biomedical applications. It also provides information on gold coatings and iridium oxide coatings for stents.

This article reviews friction and wear of various dental materials that have been studied by fundamental wear measurements, simulated service wear measurements, and clinical measurements. The materials include dental amalgam, composite restorative materials, pit and fissure sealants, dental cements, porcelain and plastic denture teeth, dental feldspathic porcelain and ceramics, endodontic instruments, periodontal instruments, and orthodontic wires. The article describes the correlations of properties such as the hardness, fracture toughness, and wear. It provides information on wear mechanism such as the sliding adhesive wear, two-body abrasion, three-body abrasion, erosion, and fatigue.

This article provides information on biomedical aspects such as active biological responses and the chemical environment characterizing the internal physiological milieu, as well as electrochemical fundamentals needed for characterizing corrosion fatigue (CF) and stress-corrosion cracking (SCC). It discusses some of the mechanical and electrochemical phenomena related to the in vivo degradation of materials used for biomedical applications. These materials include stainless steels, cobalt and titanium-base alloy systems, and dental amalgam. The article addresses key issues related to the simulation of the in vivo environment, service conditions, and data interpretation. The factors influencing susceptibility to CF and SCC are reviewed. The article describes the testing methodology of CF and SCC. It also summarizes findings from laboratory testing, in vivo testing and retrieval studies related to CF and SCC.