Asked by: Anonymous
'Mercury' fillings are actually made from an amalgam of mercury, silver, tin, copper and zinc. Unlike in an alloy, where the metal atoms are chemically bonded together, the mercury acts as a solvent. Because the mercury is not chemically bound, it gradually escapes over time. But the amounts involved are tiny and very little is absorbed by the body. Various studies have failed to find good evidence to suggest either that amalgam fillings present a significant health risk, or that they are completely safe. However, some dentists have been criticised for exaggerating the fears of mercury contamination in order to sell expensive and unnecessary replacement fillings.
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