Are amalgam fillings harmful? Are they as strong as white fillings?

30 May 2014

Are amalgam fillings harmful? Are they as strong as white fillings?

Amalgam dental fillings have been in use for over 150 years now and so far there has been no conclusive proof that they are indeed harmful. Amalgam is an alloy made from mercury with silver, tin, copper, zinc or some other trace metals in varying proportions. Because of its mercury content, concerns have been raised about its possible toxic effects not only on the users but also on the environment.

In fact, because of these concerns, Norway, Sweden and Denmark have banned amalgam fillings while Germany, Austria and Canada have discouraged their use on pregnant women, children, those with kidney problems and those allergic to metals. However, many clinical studies both private and government-funded, including those conducted by the European Commission (EU) and the World Health Organization (WHO), all found that amalgam is relatively safe. What about in the UK? Here, the British Dental Association (BDA) supports the conclusion of the EU Scientific Committee on Emerging and Newly Identified that “current evidence does not support any link between dental amalgams and diseases – neither diseases of the urinary, neurological, reproductive and immune systems nor any psychological conditions. Amalgam is a safe material to use for dental restorations….”

Mercury itself, whether in elemental form or in compounds, is of course poisonous. However, the extent of harmfulness of mercury, as with fluoride and most other chemicals, depends on the amount absorbed by the body. Very high levels of mercury harm the body, very low levels do not. The mercury levels released by mercury in amalgams fall in the very low category. Much higher levels of mercury can be absorbed from eating fish like tuna and mackerel.

While it can be said that amalgam fillings are not harmful, are they as strong as white fillings? In terms of durability, amalgam fillings can outlast white or resin-based composite fillings by as much as twice over. For this reason, most dentist still recommend using amalgams for dental restoration work on the back teeth. Amalgam fillings can better withstand the constant wear and tear that results from chewing and grinding. They need to be replaced far less often than white fillings.

White or composite fillings are basically made of a plastic material which acts as matrix and a silicate compound, such as fine glass, which serves as filler. Composite fillings are chemically bonded with the tooth during the dental restoration procedure. Because they are made of softer material, they normally get worn down a lot faster than the metal-based amalgams. Aesthetically though, composite fillings are superior. They can be made to match the exact shade and color of the teeth, making them the ideal choice for dental restoration work on the front and other visible teeth. They are strong enough for long-term biting, but not chewing and grinding, use.

Aside from durability and aesthetics, there are other considerations that must be kept in mind when choosing between amalgams and white fillings. For instance, amalgams are less expensive than white fillings and take less time at the dental office to set in place. To ensure that you make the right choice, it is probably best to consult with a dentist who is familiar with your particular condition.