As we’ve covered before, mercury has been an important refining material for centuries. Dentists are probably the most familiar with mercury. Since the 1800s, silver/mercury amalgams have been the material of choice for restorative dentistry.
Despite its widespread use, mercury is well-known as a highly toxic material. Concerns over mercury’s toxicity gave rise to an ongoing debate in the dental industry commonly referred to as the dental amalgam controversy.
Amalgams are mercury alloys. Gold and silver amalgams are very easy to make, and are an excellent material for dental fillings. However, some dental experts argue that amalgams put patients at risk because they leach small amounts of mercury into the mouth. Amalgam advocates counter that the levels of mercury a dental filling leaches (roughly 1 to 17 micrograms per day, depending on the number of fillings and level of wear and tear they are exposed to) is not enough to be a cause for concern.
OSHA mandates that working environments cannot expose workers to more than 50 micrograms of mercury per day. But again, critics contend that OSHA standards account for an average work day, not 24-hour exposure.
The arguments for and against dental amalgams go back and forth with multiple scientific studies that provide evidence in favor of both sides. Some countries, such as Norway and Sweden, have banned amalgams outright. Meanwhile, other countries keep their use unrestricted.
Alternatives to amalgams include resin composites (which last only about half as long as amalgam) and dental porcelain (which is much more expensive than even gold amalgams).
The dental amalgam controversy will likely go on for some time. But, at least it has brought the matter to light for dental patients, and enabled them to make informed decisions about which types of prostheses they want.