Urinary mercury levels before and after amalgam restoration

Urinary mercury levels and excretion rates were measured to determine the effect of dental amalgam restoration on the mercury body burden. No consistent increase in urinary mercury concentrations was found among subjects who had a single restoration, but a continuously increasing statistically significant (P < 0.05) trend, that was 33% above background levels, was detected between 9 and 12 days after restoration, in the subject with four restorations in a single day. The current findings suggested that even though amalgam restorations can cause an increase in mercury body burden, the elevation above background levels is small and thus the risks associated with the use of this material are considered minimal for the general population.