Ceramic restorations: cast metal and cast glass

Pertinent articles published between October 1989 and September 1990 related to metal-ceramic and all-ceramic crowns are reviewed. The main topic groupings are: 1) color and esthetics with metal-ceramics; 2) bond strength of metal and ceramic materials; 3) all-ceramic alternatives; and 4) the porcelain surface. Research published during this period advanced knowledge of photospectrophotometry and thermomechanical compatibility of porcelain-metal systems. Deficiencies in fit and strength for some all-ceramic systems are described. Further evidence was published supporting the efficacy of polishing porcelain. Additional documentation regarding the etching of ceramic materials, including Dicor (Caulk Company Ltd., Milford, DE) was produced. More research into use of titanium and titanium alloys as substructures for ceramic materials is required.