Castability, opaque masking, and porcelain bonding of 17 porcelain-fused-to-metal alloys.

Seventeen porcelain-fused-to-metal alloys, which represented a cross section of the various alloy types available, were evaluated for castability, opaque masking, and porcelain bond strength. The base metal alloys generally cast more completely than the noble alloys, with the presence of beryllium as an important factor for greater castability among the base metal alloys. Statistically significant differences were observed in the ability of an opaque porcelain to mask the different alloy substrates but no systematic effect of alloy type was observed. Porcelain bond testing revealed that nickel-chromium-beryllium alloys produced significantly better porcelain-metal bonds than nickel-chromium alloys without beryllium. In addition, it was found that palladium-copper alloys produced significantly better bonds with porcelain than palladium-cobalt alloys.