Many dentists have taken to using the phrase "mercury free" to describe that their practice does not use mercury amalgam fillings. This is a welcome trend, though the most recent national survey showed that half of all dentists still use this "silver" dental filling material. This article will address the distinction between "mercury free" and "mercury safe."
Mercury in Tooth Fillings
First, some background information. All "silver" fillings contain approximately 50% mercury. This is one of the most toxic substances on earth, and even a very small amount of mercury can be harmful to the body. It is a fact that dental amalgam is an inherently unstable compound, and all amalgam fillings "leak" some mercury. This is usually in the form of mercury vapor, which is inhaled or swallowed or absorbed into the soft mouth tissues. Mercury is the only metal that is a liquid at room temperature. It is also volatile, emitting colorless, odorless mercury vapor. Any increase in temperature significantly increases mercury vapor release. The same is true for an amalgam filling. It is easy to demonstrate that mercury vapor escapes from the surface of an amalgam filling, and that this escape is dramatically increased by raising the temperature. Think: hot coffee, friction from chewing food, or friction from getting your teeth polished at a dental office. For a dramatic and graphic demonstration of this mercury release from an amalgam filling, see the "Smoking Teeth" video on the web page http://iaomt.org , the official website of the International Academy of Oral Medicine and Toxicology (IAOMT). This has led to a decades-old controversy over whether this filling material should still be used in dentistry. This article won't address that issue, but rather the potential hazards of unsafely removing old amalgam fillings.
Mercury Exposure in Filling Removable
Fillings don't last forever. Whenever an amalgam filling is replaced, the process of drilling into a filling to remove it can potentially generate a tremendous amount of mercury vapor. That means a potentially harmful exposure for the patient, the dentist, and the dental assistant! This is an occupational exposure that is often overlooked, even by many dentists who consider themselves "mercury free."
There are a number of protective protocols that have been developed by the IAOMT and others, designed to protect from this unnecessary mercury exposure. Some studies have shown that the potential mercury release during this process can easily exceed the OSHA standards for safe exposure. A dentist who incorporates these effective protocols is properly protecting his or her patients. Also protected are the dentist and the dental staff. And, if the dentist has taken proper measures to protect the discharged office wastewater from mercury, the environment is also being protected. Such a dentist can be considered "mercury safe." The aforementioned IAOMT website also has a short video with a brief outline of some of the mercury safe protocols. Any dentist should adopt these procedures as a minimum of appropriate protection. There is a more detailed and extensive training available for dentists on being mercury safe from New Directions Dentistry (www.newdirectionsdentistry.com).
So, it can be said that "mercury free" is really a misnomer. All dentists who ever replace an amalgam filling are dealing with mercury in the office. How they deal with that step has a significant impact on the potential for unnecessary, harmful exposure to toxic mercury. A dentist who no longer places amalgam fillings and has learned and is committed to effective protective protocols while replacing old amalgam fillings is mercury safe. Is your dentist mercury safe?
Paul G. Rubin, DDS, MIAOMT 9730 3rd Ave. NE #205, Seattle, WA 98115 | 206-367-4712