Amalgam Briefs

March 28, 2008

DMSA treatment shows risk without benefit. Swedish researchers have investigated the effect of 14-day oral administration of meso-2.3-dimercaptosuccinic acid (DMSA) on urinary mercury excretion and the potential reduction of blood and plasma mercury concentrations. Twenty subjects, relating their symptoms to mercury from amalgam fillings, received 20 mg/kg DMSA or placebo for 14 days. Their symptoms and mood states were recorded during the study and at a check-up 3 months later. DMSA administration increased urinary mercury excretion by 65% and decreased blood mercury levels to nearly zero (0.04 micrograms/liter/day). At the 3-month check-up, however, the urinary excretion had returned to the pre-treatment level. No treatment effect of DMSA was apparent on subjective symptoms and mood state. Three subjects showed hypersensitive reactions, probably DMSA-specific, at the end of the treatment period. This placebo-controlled study provides no scientific support for diagnostic or therapeutic administration of DMSA for symptoms allegedly associated dental amalgam fillings. [Sandborgh-Englund G and others. DMSA administration to patients with alleged mercury poisoning from dental amalgams: a placebo-controlled study. Journal of Dental Research 73:620-628, 1994]

About 10% of dental patients worry needlessly about amalgam. American Dental News has reported on a survey of 1,007 patients conducted for the American Dental Association. The survey found that about 25% had heard that amalgam fillings are “bad for you” or could cause health problems. Among those who had heard the negative information, 42% said they were “not likely” to use amalgam, 38% said they were “very likely” or “likely,” 10% said they were “somewhat likely,” and 11% were “not sure.” (Due to rounding, the total did not equal 100%.) The survey also found that most people who asked their dentists about amalgam safety felt reassured.

“Amalgam illness” may reflect somatization. Researchers at the Central Institute of Mental Health, in Mannheim, Germany have compared 40 people who were convinced that their health had been affected seriously by their amalgam fillings with 43 people who did not have such a belief. The two groups did not differ with respect to the number of amalgam fillings, amalgam surfaces, or mercury levels assessed in blood, urine, or saliva. However, the “amalgam-sensitive” subjects had significantly higher symptom scores both in two tests for somatization. In addition, more subjects from this group (50% versus 4.7%) had severe somatization syndromes. (Somatization is an emotional problem characterized by persistent symptoms that cannot be fully explained by any known medical condition, yet are severe enough to require medical treatment or cause alterations in lifestyle.) “Amalgam sensitive” subjects also had a self-concept of being weak and unable to tolerate stress, more thoughts about environmental threats, and increased habitual anxiety. These psychological factors were significantly correlated with the number and intensity of the reported somatic symptoms. The researchers concluded: “While our results do not support an organic explanation of the reported symptoms, they are well in accord with the notion of a psychological aetiology of the reported symptoms and complaints. The findings suggest that self-diagnosed ‘amalgam illness’ is a label for a general tendency toward somatization.” [Bailer J and others. Adverse health effects related to mercury exposure from dental amalgam fillings: toxicological or psychological causes? Psychological Medicine 31:255-263, 2001]

No link found to Alzheimer’s disease (AD). An autopsy study that compared 68 people who had AD and 33 others who did not has found no relationship between the number and surface area of amalgam fillings, the levels of mercury in the brain, and the incidence of AD. [Saxe SR and others. Alzheimer’s disease, dental amalgam and mercury. Journal of the American Dental Association 130:191-199, 2001] An earlier study from the same group found no relationship between the number of amalgam filllings and performance on eight tests of cognitive function amoing 129 Catholic sisters who were 75 to 102 years of age. [Saxe SR and others. Dental amalgam and cognitive function in older women: Findings from the Nun Study. Journal of the American Dental Association 126:1495-1501, 1995]

Anti-amalgam attorney sued for libel. The American Dental Association has filed suit against Shawn Khorrami, charging that he targeted the ADA with an orchestrated “campaign of lies and distortion” to promote himself and his law firm. [American Dental Association sues Los Angeles lawyer for defamation; cites smear campaign as attempt to promote himself and firm. ADA news release, May 2002] The complaint seeks compensatory damages for harm suffered by the ADA and punitive damages to deter further wrongful conduct against the ADA. The suit papers state:

  • Khorrami falsely and maliciously accuses the ADA of defrauding and endangering the lives of the American public by promoting allegedly unsafe dental practices—specifically the use of dental amalgam fillings—and exerting “undue and unfair pressure” on dentists as a result of a purported “vested economic interest” of the ADA in amalgam.
  • Khorrami has falsely stated that, “When scientifically analyzed, amalgam fillings represent nothing more than a con on the U.S. population, orchestrated by the American Dental Association and its web of constituent associations and component societies.”
  • Khorrami was well aware that numerous scientific and leading consumer organizations, independent of the ADA, have concluded that dental amalgam is safe.
  • The ADA has no vested economic interest in amalgam.

TIME science writer blasts anti-amalgamists. Time magazine’s Web site has posted a column by science writer Leon Jaroff urging U.S. Representative Diane Watson to modify her views on amalgam fillings. The article was a response to Watson’s introduction of a bill to prohibit interstate commerce of mercury intended for use in dental fillings by 2007. Calling Watson “scientifically unsophisticated,” Jaroff concludes that her association with amalgam opponents “can only tarnish what has been an otherwise worthy career” and advises her to get over her “amalgam hang-up” and “learn not to be taken in by quacks.” [Jaroff, L. There’s nothing dangerous about ‘silver’ fillings: But some in Congress continue to insist there is., May 8, 2002] Although mercury by itself is classified as a toxic material, the mercury in amalgam is chemically bound to other metals to make it stable and therefore safe for use in dental applications. Quackwatch has posted a point-by-point rebuttal to some of Watson’s “unsophisticated” statements. Meanwhile, a similar California bill (AB 2270) was defeated in committee. [Berthold M. California defeats amalgam bill. ADA News 33(9):12, 2002]

Maryland anti-amalgam suit dismissed. A U.S. District Court Judge has dismissed a lawsuit seeking to prohibit the dental board from enforcing any rule or policy that “prevents, limits or intimidates” dentists from discussing “the controversy over amalgam” with patients. The suit was an attempt by supporters of “mercury-free dentistry” to block the board’s efforts to protect consumers from inappropriate removal of amalgam fillings. The judge stated that although a dentist who is disciplined would have the right to court review, the preemptive suit was too vague to provide a cause of action. [Berthold M. Maryland amalgam suit dismissed. American Dental Association news release, April 5, 2002]

American Dental Association blasts anti-amalgamists. Calling amalgam fillings “a valued treatment option,” the American Dental Association (ADA) is providing dentists with educational materials that respond to quack attacks. [Palmer C. ADA launches national educational campaign on dental restoratives. ADA News, March 10, 2002] The materials include a chart comparing the attributes of amalgam and various other restorative materials and a sample letter for patients, which states:

Dental amalgam is the most thoroughly researched and tested restorative material among all those in use. It is durable, easy to use and relatively inexpensive in comparison to other materials and therefore remains a valued treatment option for dentists and their patients. As questions have arisen about its safety related to its mercury content, they have been answered to the satisfaction of the major U.S. and international scientific and health bodies, including the National Institutes of Health, the U.S. Public Health Service, the Centers for Disease Control and Prevention, the Food and Drug Administration and the World Health Organization, among others.

The principal advantages of amalgam fillings are durability and relatively low cost.

The ADA is also speaking out against class-action suits filed in Maryland and California which claim that patients were harmed by amalgam fillings and that the ADA and state dental associations have engaged in unfair and deceptive trade practices as well as fraud and conspiracy to defraud by not informing patients that amalgam fillings contain mercury. As reported in ADA News:

The ADA said that the complaint is part of a “coordinated attempt by some to have judges decide matters of scientific debate, and stifles discussion within the scientific community, most of whose members simply do not agree with their views. The ADA is concerned that any individual suffers a serious medical condition that does not respond to conventional diagnosis or treatment. But these individuals are not helped by those who hold out false hope that removing amalgam fillings is a “cure-all” for various ailments.

There is no sound scientific evidence supporting a link between amalgam fillings and systemic diseases or chronic illness. [Berry J. ADA pledges vigorous defense’ against Maryland amalgam suit. ADA News March 4, 2002]

In another news report, the ADA referred to a California suit as “”an egregious abuse of the legal system.” [Another amalgam suit filed in California. ADA news release, March 21, 2002]

America’s most active anti-amalgamist has been Hal E. Huggins, D.D.S., whose dental license revoked in 1996. During the revocation proceedings, the administrative law judge concluded that Huggins had diagnosed “mercury toxicity” in all patients who consulted him in his office, even some without mercury fillings; and that Huggins’s treatments were “a sham, illusory and without scientific basis.”

FDA endorses dental amalgam. The U.S. Food and Drug Administration has issued a “Consumer Update” statement that “no valid scientific evidence has ever shown that amalgams cause harm to patients with dental restorations.” While indicating that research continues to look for “possible subtle and long-range health effects,” the statement notes that in 1997, the World Health Organization concluded that, “Dental amalgam restorations are considered safe, but components of amalgam and other dental restorative materials may, in rare instances, cause local side effects or allergic reactions. The small amount of mercury released from amalgam restorations, especially during placement and removal, has not been shown to cause any other adverse health effects.” Similar conclusions have been reached by the United States Public Health Service, the European Commission, the National Board of Health and Welfare in Sweden, the New Zealand Ministry of Health, and Health Canada. [Consumer Update: Dental amalgams. FDA Center for Devices and Radiological Health, Feb 11, 2002.]

Spurious amalgam suits dismissed. A New York State Supreme Court Judge has dismissed two amalgam-related lawsuits against the American Dental Association and two New York dental groups. The suits, filed in 2002 by Los Angeles attorney Shawn Khorrami, are identified in court records as Campbell vs. ADA, et al. and Kids Against Pollution vs. ADA, et al. Both suits claimed that the defendants had (a) deceived the plaintiffs and the public about health risks allegedly associated with dental amalgam; (b) concealed information about amalgam’s environmental impact; (c) promoted false scientific studies, (d) barred dentists from informing patients about alleged health effects of amalgam, (e) misrepresented amalgam as “silver” fillings, and (f) concealed their own economic stake in these alleged misrepresentations. The plaintiffs had sought an injunction, restitution, punitive damages, reimbursement for legal fees, and establishment of a fund to cover the costs of testing and monitoring the plaintiffs’ alleged “mercury poisoning.” The judge ruled that the plaintiffs lacked “personal jurisdiction” and had failed to state a claim for which relief could be granted. Similar suits are pending in California and Maryland. The suits were groundless because no evidence exists that dental amalgam is dangerous.

Scientific panel supports amalgam use. The Life Sciences Research Office, which provides scientific assessments of topics in the biomedical sciences, has reviewed scientific reports published from 1996 and 2003 and concluded that amalgam fillings are safe. The report states:

The current data are insufficient to support an association between . . . amalgam and the various complaints that have been attributed to this restoration material. These complaints are broad and nonspecific compared to the well-defined set of effects that have been documented for occupational and accidental mercury vapor exposures. Individuals with dental amalgam-attributed complaints had neither elevated urine mercury levels nor increased prevalence of hypersensitivity to dental amalgam or mercury when compared to controls. The findings of these studies suggested that individuals with complaints self-attributed to dental amalgam should be screened for underlying dental, physical, and psychiatric conditions.

The report also criticizes the use of chelation therapy to treat neurological, behavioral, or mood complaints attributed to the presence of amalgam:

Chelation challenge tests [in which a chelating agent is administered before blood or urine is tested] appear to have little utility in diagnosing individuals with amalgam-related complaints. In addition, chelation therapy appears to have limited value beyond placebo effect in individuals with dental amalgamator complaints and the chelator itself may produce side effects.

[Review and Analysis of the Literature on the Potential Adverse Health Effects of Dental Amalgam. Rockville, MD: Life Sciences Research Office, July 2004] The report is available for $50 plus shipping.

Two studies find amalgam safe for children. The Journal of the American Medical Association has published the result of two studies that found no adverse health effects from amalgam fillings. One compared the neuropsychological and kidney function of 534 children whose decayed teeth were restored using either amalgam or mercury-free materials during a 5-year period. [Bellinger DC and others. Neuropsychological and renal effects of dental amalgam in children. JAMA 295:1775-1783, 2006] The other compared memory, attention/concentration, motor/visuomotor functions, and nerve conduction velocities of 507 children over a 7-year period. This study also found that the children who received composite fillings needed 50% more restorative treatment during the later years of the study. [DeRouen TA and others. Neurobehavioral effects of dental amalgam in children. JAMA 295:1784-1792, 2006]

Anti-amalgam suit loses. A federal appeals court has dismissed a suit seeking to force the FDA to classify amalgam as a device so that it would be subject to tighter restrictions. The suit was brought by four organizations and five individuals who mistakenly believe that the mercury in amalgam fillings poses a hazard that deserves greater FDA regulation. The FDA argued that (a) its regulation is adequate, (b) the court lacks jurisdiction, and (c) the plaintiffs lacked standing to sue. The appeals court ruled that failure of the FDA to classify a device does not give rise to judicial review. [Opinion. Moms against Mercury et al. v. Food and Drug Administration. U.S. District Court for the District of Columbia Circuit. Case No. 06-1147, Decided April 13, 2007] Responding to the ruling, the American Dental Association, which was not a party to the suit, stated: “Some activist groups, relying on faulty science, tried to use the court system to force the FDA to deprive the nation’s dentists and the patients that they serve of a safe and inexpensive option for treating dental decay. . . . Dental amalgam is a safe and effective filling material.”

Major report concludes that amalgam fillings are safe. A European Commission committee has concluded that amalgam fillings pose no systemic health risks to humans and that no justification exists for removing fillings that are functioning properly. The committee’s 71-page report is available for comment until February 22, after which it could be revised before final publication. [European Commission Scientific Committee on Emerging and Newly Identified Health Risks. The safety of dental amalgam and alternative dental restoration materials for patients and users: Preliminary report. Nov 29, 2007]

This page was revised on March 28, 2008..