Amalgam fillings have been a staple of dentistry for more than a century. Millions of people have them in their mouths, but the controversy surrounding them does not cease to spark heated debates. The very presence of the suspicious metal in their teeth impels many a person to replace their fillings with plastic ones. But is mercury in fillings really dangerous?
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Why the concern?
Amalgam is the term denoting an alloy used to fill cavities in teeth partially destroyed by tooth decay. Among its constituents are silver, tin, mercury (in its liquid form), copper, and there can also be added other metals enhancing its properties. The share of mercury in the alloy is significant, making up around a half of filling weight. The main reason why the toxic metal is used in dentistry is that it is capable of binding the other constituents together and improving plasticity of a filling, so as to ensure it fills the whole cavity.
It remains debatable if the amounts of mercury leaked by such fillings can cause any harm. In the past, it was believed that amalgam never leaks mercury, because the inertness of the metal prevents the alloy from releasing it. But later it was found that as teeth are used and pressure is applied, the outer layer damaged by friction can leak small amounts of mercury in the form of vapors.
That being said, no global panic was caused by the discovery. We are constantly exposed to mercury found in water, soil and the environment in general. Most of the mercury that gets into your body, unless you work as someone who uses mercury, has food as its source. It is a matter of concern that seafood is becoming contaminated with alarmingly high levels of mercury, with some fish species even being not recommended to pregnant women due to high mercury content. As of this moment, the amount of mercury vapors absorbed by the body from amalgam fillings is estimated to be lower than the amounts ingested with food.
Studies focusing on the potential danger of mercury from dental amalgam showed little to no evidence that it can have adverse effects on health. Besides, even the level of mercury in your blood is not indicative of how much vapor has got into your organs, since it is the methylmercury from food (or organic mercury) that usually affects this parameter to a greater extent. The FDA evaluated the findings we have to date and found no reason to recommend removal of amalgam fillings unless the need arises.
More fear than mercury
In most cases, when people report developing symptoms which they attribute to mercury in fillings, it is anxiety which is the prerequisite for their occurrence, i.e. patients first find out that mercury can be dangerous and only then develop symptoms. Other than that, the FDA states, there have been no evidence-based reports suggesting that adverse effects of amalgam fillings are statistically significant, and it is now deemed safe to use in adults and children older than 6.
Still, if you do not find their reviews convincing, you can replace your amalgam fillings with newer plastic ones. They have both pros and cons, compared to amalgam: they are tooth-colored, which makes them a preferable option from the aesthetic point of view, but they are not as durable as amalgam. Besides, some mercury vapor may be released in the course of filling removal.
The takeaway is that amalgam fillings are now considered safe to use due to the lack of data suggesting the opposite. It has been used in dentistry for a long time, and even allergy cases have been very rare. Unless there is something wrong with the tooth with such a filling, it is recommended that it is not removed, since no known harm is done by it. The levels of mercury found in food are higher and a matter of greater concern.
Dental Amalgam: A Health Risk? – colgate.com
Are mercury dental fillings really that dangerous? – sciencenordic.com
About Dental Amalgam Fillings – fda.gov