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Should I worry about the mercury fillings in my teeth? © Getty Images

Should I worry about the mercury fillings in my teeth?

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Dental amalgam fillings use small amounts of mercury as a solvent. So are they safe or do they pose a significant health risk?

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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luis villazon
Luis VillazonQ&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.


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