AUTOMETALLOGRAPHIC DEMONSTRATION OF MERCURY IN RAT MOLARS

Male, adult Wistar rats were exposed to 500 mu g/m(3) mercury vapor 6 h per day, 5 days a week for 4 wk. They were subsequently killed by tr anscardial perfusion. The molars were extracted, demineralized, and em bedded in resin before sectioning. Autometallographic development was performed according to the method of DANSCHER and MOLLER-MADSEN. Mercu ry deposits were found in small amounts in several areas of the pulp, but with larger accumulations of grains in relation to odontoblasts. M ercury also could be seen in odontoblastic processes in the dentin and predentin. Our conclusion is therefore that systemic uptake of mercur y vapor leads to accumulation of mercury in the odontoblasts and that the mercury may be transported into the dentin tubules in the odontobl astic process.