[Study on occlusal wear of metal, porcelain and resin artificial posterior teeth].

Usually, the porcelain, resin and metal teeth are used as denture posteriors. However, few studies were reported on the occlusal wear of these posteriors.This study was conducted to find the degree of attrition in these different kind of artificial teeth. The three kinds of pairs of the posteriors were: (1) metal to metal teeth pair, (2) metal to porcelain teeth pair and (3) metal to resin teeth pair, and the occlusal wear was studied under a 1-kg load by impact and sliding. The degree of attrition was measured in regard to the decrease of the vertical height caused by occlusion and of the volume.Results obtained were as follows.1. The characteristics were that in all pairs the occlusal wear in regard to the height occurred rapidly in the early stage and then progressed slowly.2. In comparing the wear of volume in all kinds of artificial teeth, the metal teeth showed the least wear and the resin teeth the greatest wear.3. The occlusal wear of the resin teeth paired with several metals was the greatest in the decrease of both the height and volume compared with other pairs.4. The least wear in volume of these pairs of teeth was observed in the metal to metal teeth pair.