Our View to Mercury in Dentistry
Mercury is a silvery metal that is a liquid at room temperature and is toxic to humans and animals. It can be found in rat poison and it is used as a mold suppressor in wall coatings and paint. It is used as a fungicide in garden and lawn care products. In the electronics industry it is a component of batteries and switches, and in dentistry it comprises 50% by weight of the dental filling material known as “silver filling” or “amalgam”.
Once mercury enters the waste stream it is persistent in the environment, entering ground water and waterways. It is absorbed by algae and plankton which, when eaten by fish, is concentrated in their flesh. Ultimately fish at the top of the food chain, when consumed, pose a health risk to humans particularly the very young, the very old, pregnant and nursing mothers, and those with an impaired ability to detoxify heavy metals.
Because of these factors, “excess mercury”, that is, mercury that is a by-product of a manufacturing process including the manufacturing of amalgam fillings in a dentist’s office, is considered hazardous waste, and must be disposed of in accordance with local laws, so as to prevent groundwater contamination.
Dental amalgam is a material that has been used to fill cavities in teeth for nearly a century. When first mixed, it has the consistency of wet snow and can be easily molded to fit the shape of a hole in a tooth. Once hardened, it resists the wear and tear of chewing. However, as it ages, it tends to expand and to give off mercury. The expansion is perhaps the most common cause of teeth cracking, breaking, or splitting, often resulting in a need for a crown. Occasionally the crack will be deep enough to allow bacteria to gain a path to the dental nerve, resulting in an infection requiring root canal therapy. On occasion, the split can be so extensive as to require the tooth to be extracted. Additionally, the mercury that is given off can lead to mercury toxicity.
Mercury toxicity in humans can take on a variety of forms. Mercury accumulates in nerve cells—those that run throughout the body (peripheral), those of the spinal cord and brain (central) and in organs and glands such as the kidney and the thyroid. As the body detoxifies itself from mercury, it pushes it out through the various bodily excretions. These include hair, exhaled air, urine, feces, sweat, and milk. The damage it causes depends on where it accumulates, how much of it accumulates, and to what extent the person’s body is able to detoxify and excrete it. The University of Calgary has posted a video on YouTube that demonstrates what mercury does to the brain.
The most common symptoms of mercury toxicity in the peripheral nervous system are numbness, tingling, tremors in the fingers or toes and weakness of the limbs. The most common symptoms of mercury toxicity in the central nervous system are an inability to concentrate or form coherent thoughts, depression, blurred vision, and all forms of nervous instability. These include mood swings, insomnia, irritability, anxiety, paranoia, and the development of social phobias. Other common symptoms of mercury toxicity include a metallic taste, bad breath, loose gums or gum disease, trembling tongue, mouth ulcers or sores, loose teeth, and excessive salivation. Skin symptoms include ulcers, eruptions, skin rashes and excema-like patches.
In recent years Sweden has prohibited its use as a dental filling material, owing to concerns about toxicity and cumulative burden on the environment. Even in the United States, despite claims from industry and from the American Dental Association attesting to its safety, manufacturers of dental amalgam provide warning labels indicating that this material should not be used in children under six or in expectant mothers.
The issue of mercury amalgam has polarized the dental field. The vast majority of dentists agree with the American Dental Association that it is safe, while a vocal minority issues calls for its wholesale removal from every mouth in America, in order to prevent or reverse a multitude of chronic diseases. Where, in this debate, lies the truth?
Dental amalgams give off small amounts of mercury every day but the degree of toxicity from this varies from person to person. Some people detoxify and pass mercury with little or no difficulty or have cells that resist its absorption. Others can have great difficulty ridding themselves of even small amounts of mercury so that the traces of it coming off of dental amalgams tends to steadily accumulate in their tissues.
Because the symptoms of mercury toxicity are so varied, and because they may take years or decades to develop, rarely is mercury looked at as a culprit; and rarer still is the dentist who reflects on the chronic health problems of his or her patients and thinks that these dental fillings might have something to do with them.
Our office deals with dental mercury in four ways:
- First, we don’t use dental amalgam as a dental filling material. This keeps us from perpetuating the problems associated with the manufacture and disposal of mercury in the environment, with the problems associated with amalgam induced tooth breakage and the potentials of mercury toxicity.
- Second, we test every patient using Autonomic Response Testing (also known as muscle testing) in order to gauge to what degree his or her body is troubled by mercury.
- Third, we follow a careful protocol whenever we remove dental amalgam to minimize your exposure to mercury, protect your body from mercury absorption and to be sure that you are optimally detoxifying yourself.
- Fourth, we carefully collect the waste dental amalgam that we remove from teeth using a state of the art filtration system to keep our local groundwater free of mercury.