The masking ability of an opaque porcelain: a spectrophotometric study.

The ability of opaque porcelain to conceal the color of noble alloy or nickel-chromium substructures was compared. A 0.5-mm layer of opaque porcelain was fused to the sample metals and chromatic analyses were carried out with a color analyzer. Color measurements were made as the thickness of porcelain was reduced in 0.1-mm increments. The true color of the opaque porcelain was apparent in ceramic thicknesses greater than 0.3 mm. The opaque porcelain was more efficient at covering noble alloys than nickel-chromium alloys.