4) Other materials safe?

The Patient Asks, "Are these other materials safe?"

The ADA Answers, "The ADA has approved a number of them as 'safe and effective,' and I have confidence in that seal of approval. The profession has been using amalgam for more than 150 years, and some of these newer materials have been around for only a decade or less, so we don't have the long-standing history of safety with them that we have with amalgam."

The ADA answer is misleading. There is no ADA certification for the mixed amalgam as, "safe and effective." The ADA has maintained that mixed dental amalgam is a reaction product manufactured by the individual dentist and therefore cannot be certified and it is the responsibility of the individual dentist to determine the efficacy of the materials and their appropriateness for each patient. [38] One reading this paragraph is given the distinct impression that dental amalgam has the ADA seal of approval as, "safe and effective" and has been certified. What has been certified is the purity of the mercury and the composition of the silver alloy.

5) 150 years of successful use?

In the statement of confidence in amalgam, the ADA no longer maintains that the safety of this dental implant has been scientifically proven but relies on the anecdotal opinion of 150 years of "successful" use.

ADA states, "The strongest and most convincing support we have for the safety of dental amalgam is the fact that each year more than 100 million amalgam fillings are placed in the United States."

1. This is a chilling thought. It should be cause for concern that approximately seventy-two tons of mercury are used annually in dentistry, much of it being implanted in the teeth of North Americans without any proof of safety. "The absence of evidence is not evidence of absence" (Carl Sagan). Historically numerous common products were thought to be safe; for example asbestos, lead, and DDT. In each case the scientific concerns were immediately discounted by the industry responsible for the production or use of the material and often the assertions of safety were initially supported by the responsible government agencies. After a period of time as the evidence became overwhelming and legal liability impossible to ignore, they were regulated or withdrawn from the market. Each of these products demonstrated pathology after a latency period of chronic low dose exposure as does mercury. Moreover, the resulting pathology from mercury tends to be of a medical nature and would not be apparent to most dentists. Thus, in the case of amalgam mercury exposure, if a health problem should exist, most dentists are not trained to diagnose such a condition and most physicians would not be aware of the possibility that mercury from fillings might have induced the pathology.

{My own note - how much of that 150 years really count? See my above notes - ie. really intensive re-drilling of amalgam fillings has occurred post-antibiotics, together with the rising access of the population to previously expensive health care..}

6) Blatantly false statement

The ADA statement of confidence in amalgam claims, "The Food and Drug Administration in 1987 classified mercury amalgam as a Class I dental device."

The ADA statement is FALSE. In fact, the FDA in 1987 classified the alloy and the mercury components of mercury amalgam separately. They refused to classify the set amalgam reaction product.

7) Remove current amalgams?

The Patient Asks, "If there is any question at all, wouldn't it be wise for concerned patients to simply have their amalgam fillings removed and replaced with other materials?"

The ADA Answers, "Unless the patient suffers an immediate adverse (allergic) reaction to an amalgam, a reaction that does not resolve in a short time, it is not advisable to have amalgam fillings removed." Since 1984 the ADA has claimed that the incidence of hypersensitivity to mercury is less than 1%. [39]

The ADA answer is both false and misleading. This position is in stark contrast to the published scientific literature both before and after 1984. It has been reported that cutaneous (skin) allergy to mercury occurs in approximately 5% of the general population. Studies of those with amalgam fillings finds that between 2% - 35% test hypersensitive to mercury. [40 41 42] None of the experimental subjects without dental amalgam tested positive for allergy to mercury. The development of this adverse reaction may not be immediate but, research shows that the incidence of allergy gradually increases with time and onset may be delayed five or more years. [43]

8) Misleading bibliography

The ADA supports their argument with five references. Bibliography:

1) Reinhardt, J.W. Risk assessment of mercury exposure from dental amalgams. J. Public Health Dent 48:172-7, 1988

2) Langan, D.C., Fan, P.L., Hoos, A.A. The use of mercury in dentistry: a critical review of the recent literature. JADA 115:867-880, 1987

3) Fan, P.L. Safety of Amalgam. CDA J 15:34-6 1987

4) The Mercury Scare. Consumer Reports, March 1986

5) Council on Dental Materials, Instruments, and Equipment and Council on Dental Therapeutics. Safety of amalgam-an update. JADA 119:204-5 1989

The ADA bibliography cited is misleading. The total lack of valid science to support the continued use of amalgam is apparent in the ADA Special Reports bibliography. They cite only review articles and lay media reports and no primary research into either animal or human physiological or immunological reaction to dental amalgam metal. The review articles and lay reports rely almost exclusively on measurements of mercury from blood, and urine to support their conclusions. On page 396 of the Special Report the author partially quotes the conclusion of the 1984 NIDR Workshop on the Biocompatibility of Metals in Dentistry, "and there appears to be little correlation between (mercury) levels in urine, blood, or hair, and toxic effects." They thereby negate the validity of their own bibliographical references.

The scientific literature clearly does not support such an approach. Quoting directly from the research, "Urinary mercury levels may give some indication of the degree of exposure. They are of limited value in the diagnosis of poisoning, since high levels can be found in human subjects who are symptom-free, and low levels in those exhibiting marked evidence of mercurialism. It has been suggested that, in some cases, failure to excrete mercury is a factor in the development of poisoning. Those investigators that have studied the subject are in almost unanimous agreement that there is poor correlation between the urinary excretion of mercury and the occurrence of demonstrable evidence of poisoning." [44]

Moreover, none of the articles referenced in the ADA bibliography contain hard research. They merely cited other primary research papers to support their divergent conclusions. Many of the primary research scientists referenced in the review articles did not conclude that amalgam was safe. This bibliography would therefore be very misleading to anyone not familiar with the current research.

9) ADA brochure misinforms

The ADA utilized this Special Report to promote the sale of their patient education brochure on the safety of dental amalgam titled, Filling Dental Health Care Needs (W186). This brochure makes many of the same claims and factual errors found in the special report.

It is the conclusion of this academy that the use of this brochure alone would misinform dental patients regarding the potential risks they might undergo from having this material implanted and leave the dentist at risk of legal liability and guilty of negligent misrepresentation.

Also make sure to read these books: Poison in Your Teeth: Mercury Amalgam (Silver) Fillings...Hazardous to Your Health! and Mercury Detoxification by Tom McGuire