[Current types of ceramics available or in use].

For years, dental profession tried, to find an ideal material and technique, for improving esthetic and functions. The use of porcelain fused to metal crowns, offered the opportunity to build up esthetic crowns on anterior and posterior teeth; however the metal substructure of porcelain fused to metal crown prevent us in many cases to achieve an ideal esthetic, as far as translucency is concerned. The ceramic built up on an alumina core, and the new castable ceramics seam to eliminate this problem, but the laboratory procedures are time consuming and complex, and their mechanical strength are still questionnable.