Dear Toothy,

Amalgam is a hard-wearing mixture of silver, mercury, and other metals which is generally used for filling cavities in back teeth. They have a limited longevity and may need to be replaced after about ten years.

Dental amalgam is backed by 150 years of safety and effectiveness. Based on the results of extensive scientific research, the American Dental Association (ADA), the U.S. Food and Drug Administration (FDA), the U.S. Public Health Service (PHS), the Environmental Protection Agency (EPA), the National Institutes of Health (NIH), the World Health Organization (WHO), the National Institutes of Dental Research, and the FDI World Dental Federation continue to support the safety of amalgam as a dental restorative material, except in the very rare case of allergic reaction to something in the amalgam mixture. According to the American Dental Association, "for the vast majority of dental patients, mercury containing amalgams present no health hazards." Furthermore, the ADA states that "people are exposed to more total mercury from food, water, and air than from the minuscule amounts of mercury vapor generated from amalgam fillings."

There's no evidence to support the claim that the mercury used as a hardener in silver dental amalgams can leach into your bloodstream in significant amounts and thus, supposedly, cause a variety of conditions, ranging from insomnia to multiple sclerosis. Researchers conducting tests on 1100 people with amalgams found levels of mercury in their urine of less than twenty micrograms per liter. According to the American Conference of Governmental Industrial Hygienists, there is no need to be concerned unless levels exceed 150 micrograms. There also has been no convincing evidence that it's dangerous to breathe in the vapor when fillings are being ground down in a dental procedure.

Alice

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