Porcelain teeth, some of which contained uranium compounds for aesthetic purpose, have been widely used in dental clinics. Recently, the hazardous effects by uranium radiation were suggested.In the present study, the authors carried out the determination of uranium concentrations of four major brands of porcelain teeth marketed in Japan using the fission track method, and the absorbed doses of oral tissues were calculated by the authors' introduced formula for calculation of alpha radiation.Average uranium concentrations of the brands studied were determined 3.6ppm (0.33-10ppm, Japan), 18ppm (0.69-81ppm, Japan), 9.4ppm (2.5-14ppm, Japan) and 82ppm (11-205ppm, U. S. A.), respectively. The corresponding dose equivalents at the surface of oral mucosal membrane were 2.9rem y-1, 14rem y-1, 7.6 rem y-1 and 66rem y-1.