An in vitro investigation of the wear of enamel on porcelain and gold in saliva

This study compared enamel wear against low-fusing porcelain (Procera Ah-Ceramic) with the wear against feldspathic porcelain (Ceramco) and gold alloy (Olympia). Human enamel abraders were polished to a 3 mu m variance on silicon carbide paper. Five enamel abraders were abraded against five disks that were fabricated from (1) gold alloy polished to 1 mu m variance, (2) autoglazed feldspathic porcelain, and (3) autoglazed low-fusing porcelain. The enamel sample was tested in human saliva in a wear machine with a constant load of 1 pound during 10,000 rotational cycles. The amount of wear was determined with a stereomicroscope at magnification x64. Significant differences in mean enamel wear were found when abraded against Olympia gold (9 mu m), Procera Ah-Ceramic (60 mu m), and Ceramco feldspathic porcelain (230 mu m). Significant differences in restorative material wear were found between Olympia gold (0.32 mu m) and the porcelain materials, Procera AU-Ceramic (4.3 mu m) and Ceramco feldspathic porcelain (3.7 mu m).