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Mercury/Silver Fillings
An Historical Perspective and Update
By Bill Wolfe D.D.S., N.M.D.
What is the only metal that is a liquid at room temperature and vaporizes
very easily at body temperature?
What metal is the
second most bio-incompatible, naturally occurring element?
What metal makes
up approximately 50% of the 'silver' fillings in your mouth?
The answer to all of
the above . . . .
MERCURY
About 1830, a revolutionary
new dental restorative material called 'amalgam' was introduced to the
United States. This amalgam was developed in England and France and contained
silver, tin, copper, zinc and mercury. The amalgam fillings were not openly
embraced by organized dentistry in America, and in 1840, members of the
American Society of Dental Surgeons were required to sign pledges not
to use mercury fillings. In fact, several New York city dentists were
suspended from this organization in 1848 for 'malpractice for using silver
mercury fillings'. In 1859, a new organization was formed as a result
of the internal strife over the use of mercury in dentistry - the American
Dental Association.
So what chronological events have occurred which have resulted in the
current controversy over mercury in fillings, much the same as 160 years
ago?
History of the Dental Amalgam
Controversy
1819: Invention of
silver/mercury amalgam by the English chemist, Bell.
1826: First use of dental amalgam in England and France.
1830: Amalgam fillings first used in the U.S.
1840: Organized dentistry denounced the use of amalgam as a poor filling
material, especially due to concerns about mercury poisoning.
- American Society of Dental Surgeons formed. Members were required to
sign a pledge promising not to use mercury fillings.
1859:American Dental Association was formed. The ADA supported the use
of silver amalgam then as the filling material of choice, as it still
does today.
1926: The German chemist, Dr. Alfred Stock researched mercury poisoning
and identified through his research that silver amalgam fillings in the
mouth were a source of mercury vapor.
1957: Dr. Karl 0. Frykholm's studies in Sweden concluded that when saliva
covered the amalgam filling, mercury is no longer released.
1976: The Federal Drug Administration pronounced acceptance of amalgam
fillings and "grandfathered" their approval under the G.R.A.S.
(generally recognized as safe) category, due to its long term usage.
1979: Research began appearing in the literature documenting that mercury
vapor was constantly being released from amalgam fillings, especially
when the flllings were stimulated by chewing, brushing, or heat exposure.
1984: Human autopsy studies were published which demonstrated that the
amount of mercury found in brain and kidney tissue was directly related
to the amount of mercury amalgam fillings in the teeth.
- Significant research at the University of Calgary School of Medicine
demonstrated that mercury from dental amalgam fillings could be found
in the blood and tissues of pregnant mothers and their babies within a
few days.
1990: The first controlled research on the effects of dental amalgam were
published. The research cited significant effects of mercury amalgam on
various tissues and organs in experiments with monkeys and sheep. The
media became involved when the T.V. show "60 Minutes" aired
a segment entitled, "Is There A Poison In Your Mouth?"
1991: Many D.A.M.S. (Dental Amalgam Mercury Syndrome) support groups became
more active in consumer awareness of the mercury amalgam issue.
- The first products liability suit against a manufacturer of amalgam
in connection with mercury poisoning was filed in Tennesse. Consumer activist
groups along with concerned legislatures began to introduce "informed
consent" legislation, whereby a dentist would be required to inform
the patient of the contents of the amalgam filling and the potential harmful
effects of the mercury component (Such legislation was voted down in committee
in New Mexico after being unanimously passed the previous week by the
same committee).
Sweden declared that
amalgam will be banned. (The majority of dentists are voluntarily not
using amalgams in pregnant women).
A law suitwas filed (by approximately 100 dentists) against the American
Dental Association for fraud and breech of contract regarding the amalgam
issue.
The F.D.A. "reviewed"
amalgam as a filling material and declared that current evidence was insufficient
to condemn amalgam. They did recommend, however, further studies be done.
May: The Illinois House of Representatives passed a Right-to-Know, Informed
Consent Resolution. This resolution directed the Illinois Department of
Public Health to examine the existing research and literature and to make
a report to the Illinois General Assembly of its findings as well as recommendations
as to how patients should be informed of these findings. The resultant
position paper reflected the ADA's position on amalgams as being safe.
A medical research team at the University of Kentucky established a probable
relationship of mercury exposure from silver amalgam dental fillings to
Alzheimer's disease and cardiovascular disease.
University of Georgia microbiologists determined that mercury from fillings
inhibits the effectiveness of antibiotics.
World Health Organization reported that exposure to mercury from amalgams
is higher than from fish, seafood, water and air.
August: The National Institute of Health Technology Assessment Panel on
Dental Materials issued a statement that amalgams are safe.
October: The Washington Dental Disciplinary Board proposed dental ethics
legislation that would have made it unethical and a punishable offense
for dentists to replace "clinically serviceable" dental amalgam
fillings for health purposes. The proposal did not pass.
1992: February: At the annual meeting of the Society of Toxicology, medical
scientists presented five studies demonstrating adverse health effects
of mercury exposure from amalgam fillings.
The California State Senate passed an "informed consent" bill
regarding the use of dental amalgam. The bill (SB934) must still be approved
by the State Assembly and the Governor.
The German Federal Department of Health banned the manufacture and sale
of one specific brand of dental amalgam filling material.
A logical approach
to the amalgam issue would be for the F.D.A. to reclassify amalgam to
a Class III device. Such a classification would require the manufacturers
to submit the results of safety and effectiveness research in order to
continue its manufacture. In other words - to prove that amalgam is safe
- the same request that the F.D.A. has made of silicone breast implant
manufacturers.
The World Health Organization,
O.S.H.A., N.I.O.S.H., etc, all agree that mercury's an environmental poison
and have established specific occupational exposure limits. The Environment
Protection Agency has declared amalgam removed from teeth to be a toxic
waste. Even the American Dental Association warns that amalgam filling
material is hazardous to dental office personnel, but is safe in patients'
mouths.
The most puzzling thing
about this 160 year old controversy is that it is still a controversy.
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