Dentists have filed suit agains state regulators over what they contend is a gag order preventing them from discussing with patients the potential health hazards of the most common form of dental filling.
The central problem is silver amalgam, that is routinely put in dental fillings. The fillings are actually about 50% mercury, with some silver, copper, tin and zinc mixed in.
Mercury opponents argue that mercury vapor coming from the fillings seeps into the body, contributing to a range of health problems from fatigue and immunity suppression to neurological diseases such as Parkinson's and Alzheimer's.
The suit was filed in federal court in Greenbelt, Md., by five dentists and seven patients claiming injury from the mercury in their fillings. The plaintiffs argue that dental regulators use "control of dental licenses to punish, or to threaten punishment of, dentists who criticize mercury amalgam," violating the dentists' First Amendment rights.
In 1999, for example, the suit claims that the Maryland Board of Dental Examiners ordered dentist Bill DeLong to stop testing his patients to determine whether mercury vapor was coming off their fillings. (The case was eventually dropped.)
The dentists' attorney, Charles Brown of Washington, D.C., says the plaintiffs want the court to order licensing boards to stop enforcing any policy that "prevents, limits or intimidates dentists" from discussing the controversy or advocating "mercury-free" dentistry. The suit also seeks certification as a defendants' class action naming 50 of the country's 52 licensing agencies.
The dental establishment maintains that some dentists have used the controversy over mercury's safety to encourage patients to remove amalgam fillings and replace them with more expensive materials such as gold, porcelain and a tooth-colored resin composite. Resin, the least expensive alternative, costs as much as 25% more than fillings containing mercury.
Nevertheless, state legislatures in New York and Maine are debating bills that would require dentists to disclose to patients the makeup of their fillings.
New York Assemblyman Richard Brodsky's bill would also ban dentists from filling cavities in pregnant women and children with mercury.
A Vermont bill would require dental offices to track how much mercury they use in fillings. And California's dental board is considering spelling out the pros and cons of different fillings in a consumer fact sheet.
Minnesota's dental board may also become more amenable to alternatives to mercury. In 1999, Minneapolis dentist Ronald King, who advertises "dental care that integrates conventional and alternative philosophy," was appointed to the board by Gov. Jesse Ventura. He is now on a committee that hears complaints about dentists, including mercury-free dentists. Dr. King says other board members now see him "as a colleague instead of a weird guy with his own agenda."
The Amalgam Wars began in the mid-1800s, when dentists first started using mercury-based material to treat tooth decay. Originally, it was the dentists who used mercury who came under fire from colleagues who didn't believe it was as safe as gold or tooth extractions. But soon, mercury became the material of choice, mostly because it was cheaper and easier to use -- and it was less painful than having hot gold poured into a tooth.
In 1976, when the U.S. Food and Drug Administration began regulating medical devices, it grandfathered in mercury-based fillings as an approved dental material.
The ADA, which once had a patent on mercury fillings, maintains that mercury is safe once it is mixed with other metals and set in teeth, but it warns dentists about the "potential hazard of mercury vapor" when they handle the material.
In a 1999 report, the Agency of Toxic Substances and Disease Registry, a division of the US Department of Health and Human Services, concluded there is no apparent health hazard but urged further study to "determine the possibility of more subtle behavioral or immune-system effects, and to determine the level of exposure that may lead to adverse effects in sensitive populations."
Fillings could contribute as much as 75% of a person's daily mercury exposure, the report said, noting that the vapor is released during chewing and because of corrosion.
Judith Baker, a South Bend, Ind., accountant and a plaintiff in the Maryland suit, was so sick she had her gallbladder removed in 1999. But another doctor later diagnosed her with mercury poisoning stemming from a new filling containing mercury and the replacement of two old mercury fillings with a larger one.
Ms. Baker says she was skeptical and had her well water tested for mercury and her house tested for fumes before asking a dentist to remove her fillings earlier this year. She says she is starting to feel better after going through mercury detoxification treatment.
Boyd Haley, a University of Kentucky chemist who has published several studies using rats and human brain samples, says his work shows that brain tissue exposed to mercury develops the same biochemical defects seen in Alzheimer's disease.
But even Dr. Haley doesn't theorize that the fillings cause significant adverse health effects in everyone. "Certain patients, due to genetics or illness or other toxic exposures, could be more sensitive to the amount of mercury normally released from dental amalgams," he says.
The ADA responds by pointing to a study published in its journal that concluded that mercury in fillings "does not appear" to be a factor in the development of Alzheimer's disease. But one of the study's authors, chemist Charles Cornett, is wary of that conclusion. He says the study failed to evaluate how different people process mercury, among other factors.
Two large clinical trials sponsored by the National Institutes of Health are now under way with the goal of determining how school children with and without mercury fillings develop. Results of those studies won't be known until at least 2005.
Meanwhile, the Maryland board is proposing a new rule that states that removing "serviceable mercury amalgam restorations" is unprofessional without informed consent that includes telling the patient that "there are no verifiable systemic health benefits resulting from the removal."
The Wall Street Journal May 10, 2001 Page B1
