Clinical discrimination between autoglazed and polished porcelain surfaces

Precementation refinements of porcelain-fused-to-metal crowns often require reglazing or polishing of the porcelain surface. This study was done to determine whether visual inspection differences exist between glazed and polished porcelain surfaces. Prosthodontists, general dentists, and students (six in each group) rated esthetic properties of 12 porcelain-fused-to-metal crowns. All crowns were initially autoglazed. For phase 1 observations, six crowns were air abraded and polished and six retained their glazed surface. For phase 2 observations, the surface treatments were reversed. At both observations, crowns were rated on 5-point Likert scales for outline form, porosity, smoothness, reflectance, texture, dullness, defects, and general esthetic appearances. Phase 1 polished and glazed crowns had different means for outline form sharpness, porosity, reflectance, dullness, and general esthetic appearance. Phase 2 crowns were different for dullness. Polished and glazed crowns alike were more dull at phase 1 than at phase 2. Glazed crowns were different between phases for reflectance and general esthetic appearance. All reported differences were significant at p less than .01. Significant differences occurred among raters with polished and glazed crowns for several variables.