Bite Dental Studios Brisbane City Dentist



Mercury mouth: are amalgam fillings safe?

Dental amalgam (silver fillings) has been used as a reliable, efficient, long-lasting and safe filling material for over 100 years. While you may have seen or heard commentary suggesting that the use of dental amalgam fillings is dangerous, rest assured these comments are not supported by scientific fact. Health experts and institutions world-wide support the use of amalgam fillings, but concern over the safety of this material persists. Here’s what you need to know.In a statement released by the U.S. Food and Drug Administration (FDA) in 2009, amalgam dental fillings, which contain mercury along with other metals, were pronounced safe for most adults and children over 6 years of age. However, in December 2010, an FDA advisory panel of scientists and other dental health experts met again to review the safety information of amalgam fillings. The panel upheld the 2009 ruling, but it also urged the FDA to continue to review and evaluate their safety, suggesting the issue still isn’t definitively settled. Since then, a whole lot of confusion has ensued. Many people are wondering: Are my fillings really safe?

Amalgam dental fillings have been the mainstay of cavity fillings for more than 150 years. It is the most well researched of all dental materials. The definition of ‘amalgam’ is in fact a mixture or amalgamation of metals. And so, amalgam dental fillings are a mixture of roughly half liquid mercury and half a combination of silver, tin, and copper. It is important to understand that once the amalgam filling has mixed and is set, there is no longer any pure mercury present—a new compound metal has been formed that is stable and does not ‘leak’ mercury.

It is concluded however that the main exposure to mercury in individuals with amalgam restorations occurs during placement or removal of the fillings. According to the European Commission’s Scientific Committee on Emerging and Newly Identified Health Risks (2008) “The removal of amalgam restorations will transiently increase the exposure of individual patients to concentrated mercury. Therefore, there is no clinical justification for removing clinically satisfactory amalgam restorations, except in patients suspected of having allergic reactions to amalgam constituents.”

To put this exposure in perspective, the exposure of mercury associated with dental treatment is less than eating a 95g can of tuna!

While there are still public concerns about the safety of amalgam fillings, the position of both the FDA and the Australian Dental Association (ADA) is this: They are safe. “There are some who feel the mercury contained in these fillings is toxic and could potentially jeopardize a person’s physical health,” says Dr. Vincent Mayher, former President of the AGD. “Currently neither the FDA nor the ADA supports these claims, which are usually anecdotal and not based on hard or proven science. It is difficult to determine why some individuals feel that these fillings are harming them. It’s possible that these claims first started as a result of situations of true metal allergies that, while rare, are a valid cause for concern.” It is noteworthy, however, that the FDA reclassified dental mercury from a class I device to a class II device that requires special considerations and the need to warn patients of the potential risks involved.

I understand the facts but I’d still rather have all the metal removed from my mouth

Tooth-coloured fillings, for example ‘resin composite’ and ‘glass-ionomer’ may be an alternative to amalgam fillings. However, choosing tooth-coloured fillings because they are metal-free and more aesthetic may not be in the best interests of your tooth. Resin composites and glass-ionomers can be technically more difficult to place, more expensive and may not last as long as amalgam. Replacing any filling unnecessarily for improved appearance results in additional tooth loss and weakening of the remaining tooth structure. Remember also that risk of mercury exposure is highest during the placement and removal phases. Unless there is a legitimate clinical need to replace your filling, you are better off keeping the one you have got.

What should I do if I’m not sure?

The first step should always be to talk to your dentist.

Ask us any questions you have about amalgam or alternative filling materials until you are comfortable you have selected the option that is best for you and your tooth.  If you need any more information the ADA has extensive resources on their website www.ada.org.au.