The wear of dental porcelain in an artificial mouth

Simulated occlusal wear studies in an artificial mouth involving enamel occluding on porcelain demonstrated a high coefficient of wear for dental porcelain; in agreement with other workers, an abrasive wear process is postulated. Volume loss due to wear showed good linearity as a function of the number of masticatory cycles with slight flattening at higher masticatory levels. However, the depth of wear curve showed a pronounced deviation from linearity with flattening of the wear rate with time. A parabolic relation exists between volume and depth of wear and correspondingly between time and depth. Based on the coefficient of wear, the intrinsic wear of porcelain appears to be about one order of magnitude greater than that experienced by dental amalgam.