Occlusal contact wear of prosthodontic materials. An in vivo study.

The wear of gold, porcelain, and heat- and light-cured resins in occlusal contact with resin and porcelain teeth has been studied in vivo. Both weighing of removable segments of fixed partial prostheses and a replica technique allowing scanning electron microscope observations of the worn surfaces were used. The results showed that all materials had the greatest loss of substance when the opposing teeth were of porcelain. The heat-cured, unfilled resin was the least wear-resistant material, followed by light-cured resin, porcelain, and gold. The heat-cured resin showed a combined tribochemical and fatigue type of wear. The light-cured resin and porcelain showed mainly a fatigue type of wear, whereas gold showed a combined abrasive and fatigue type of wear.