Ceramics or Porcelains are chemically intimate mixtures of metallic and non metallic elements, that allow ionic (K2O) and/or covalent bonding (SiO2) to occur. The most common ceramics used in dentistry are alloys of 3 main metallic oxides (SiO2, Al2O3, K2O). Composition of Dental Ceramics and Dental Porcelain: 1) Feldspar: 60 to 80%. this is a [&hellip