9.3. Classification according to Processing Techniques
A more convenient and simple way of classifying ceramics used in dentistry is the classification according to how they are processed.
1. Glass based systems produced by mixing powder-liquid,
2. Milled or pressed glass-based system blocks and
3. CAD/CAM or paste, day processed, mostly crystalline (alumina or zirconia) systems.
Glass based systems produced by mixing powder-liquid are ceramics produced for veneer cores made of metal, alumina or zirconia. However, it can be used for ceramic veneering on a resistant day or platinum foil technique.
Blocks produced with or without crystalline filler are compressible and workable versions of with IPS Empress and the materials in the Vitabloc Mark II classification for CEREC**. These materials are appropriate for inlay and onlay restorations, anterior crowns and veneers and possibly onlay crowns.
Mostly or entirely crystalline alumina or zirconia based systems formed by CAD/CAM or paste/day are Procera and glass infiltrated In-Ceram which are solid sintered alumina. These materials work well as a core for veneered single crowns with a powder-liquid glass-based material (ceramic).
*Ivoclar Vivadent, Lichtenstein
**Sirona Dental System Gmbh, Bensheim, Germany