Dental amalgams are primarily made of mercury, silver, copper and tin. They have been used in dentistry for over 150 years and remain the filling material of choice. Dental amalgams offer important advantages. They are inexpensive and very durable, lasting up to 15 years for some fillings. They seal the tooth well, reducing the repeat rate of cavities. Lastly, they resist the repeated chewing pressure. Its main drawback remains its silvery colour, which does not please everyone.
Dental amalgams release mercury vapor, particularly when chewing. This phenomenon has been known since the late 70s. According to scientific literature, the quantity of metallic mercury released is still well below the toxicity threshold. Not to mention that people also absorb mercury in other forms from the environment on a daily basis. This organic mercury can be found in the air we breathe, water and foods such as fish
Health Canada recommends not using amalgams in the following cases:
- Those allergic to mercury. In fact, mercury can cause hypersensitivity reactions in about 2-3% of people. Real allergies to mercury however are rare, to less than 1% of people. A skin test and an oral examination will confirm whether a person is allergic to mercury.
- People who suffer from kidney disease and those wearing braces or other orthodontic metal apparatus.
- Pregnant women.
- Children who still have their first teeth. The toxicity threshold of mercury is not yet known in children
The “Ordre des Dentistes du Québec” does not recommend the replacement of amalgams in good condition by other filling materials.
Lastly, dental offices within the Greater Montreal area are equipped with amalgam separators, which allow for proper disposal of amalgam waste into the environment.