The Detractors
Germany was the first to issue concerns about amalgam in 1993. In 1997, the Swedish National Board of Health
did not find conclusive evidence concerning mercury fillings but recommended that they be phased out. Other
European nations have followed suit, including Austria and Denmark. California state law now requires that a
disclosure form be signed by all patients who are going to have fillings, making them aware of the chemical
composition of what is placed in their mouths.
Health Canada considers amalgams to be safe for general use but advises that “people with impaired kidney
function” or who have neurological conditions should consider alternatives. As well, they recommend that pregnant
women and those with allergies to metals may want to delay dental work using mercury.
Symptoms of mercury poisoning can range from fatigue to dizziness, vision problems, depression, memory loss,
headaches, and problems with digestion. The more serious effects include kidney and liver complications, infertility
and heart problems.
Some on this side of the issue claim that mercury fillings contribute 3 to 4 times more mercury to our bodies than all
other environmental sources combined. They point out that amalgam fillings placed since the 1970’s (with a higher
copper content) release many times more mercury than older style amalgam fillings. This release of mercury vapor
is exacerbated in individuals who exhibit Bruxism (teeth grinding). In addition, they believe that because the metals
are not bound together well, that direct transfer of mercury into the body is possible.
Holistic dental practices have sprung up that “specialize” in removal of amalgam fillings. They often do toxicology
testing through blood, hair, or air samples taken from your mouth after chewing. Some of these practices claim
ties with Alzheimer’s Disease, Multiple Sclerosis, Parkinsons’ Disease, and many others. Consumer's Reports has
warned against some of these "mercury removal" dental practices.
The Supporters
The groups supporting the safety of amalgam fillings are formidable. They include the national Institute of Dental
Research, National Bureau of Standards, The American Dental Association (ADA), The Academy of General
Dentistry (AGD), most of the state dental societies, and most teaching colleges.
One of the significant problems with this issue is there does not seem to be any way of proving that mercury is the
sole cause of detectable damage to the human body. To prove for instance that mercury fillings are the cause of
kidney damage, we would have had to maintain a sterile environment over the course of our lifetimes. We would
have had to ensure that there was no exposure to thousands of chemicals and pollutants.
The position of the American Dental Association is summarized as follows (from their website)
“Dental amalgam is considered a safe, affordable and durable material that has
been used to restore the teeth of more than 100 million Americans. It contains a
mixture of metals such as silver, copper and tin, in addition to mercury, which
chemically binds these components into a hard, stable and safe substance. Dental
amalgam has been studied and reviewed extensively, and has established a record
of safety and effectiveness. Depending on treatment needs, it is one material
available to dentist and patients when considering restorative options”
Organizations such as the ADA point out that scores of lawsuits, in many states, have been dismissed. They further
point out that the FDA’s Dental Products Panel has found no valid data to demonstrate clinical harm to patients or
that having them removed would prevent adverse health effects or reverse the course of existing disease. (The
FDA’s most recent reaffirmation of amalgam’s safety was published on December 31, 2002).
Our Position
Quality of restoration
When high quality composite filling materials became available they solved several problems that had existed for a
century with amalgam fillings. First, they were white! It had been every Cosmetic Dentist's dream to be able to
offer patients restorations that looked like their natural teeth. Indeed, patients were thrilled. Not only were
amalgam fillings a silver color, but they often corroded and became black over time.
Amalgam does not adhere to tooth surfaces. When a dentist places an amalgam filling he must drill deeply into the
softer dentin area of the tooth and drill undercuts into the healthy tooth. This large "cavity" has the amalgam
stuffed into it, and the undercuts keep it from falling out. As a result the tooth is permanently weakened.
Modern composite fillings bond to the tooth surfaces. As a result, the dentist can prepare a smaller cavity in the
tooth because it does not have to be undercut. A properly filled tooth is often stronger after restoration than the
decayed tooth was. This is a significant advantage over amalgam filings.
Amalgam fillings expand and contract due to heat and cold, while the materials in composite fillings are actually
used as insulators. The expansion of amalgam fillings can contribute to tooth cracking. The contraction of the
fillings allows "leakage" whereby decay producing bacteria can get under the filling. All fillings have a finite service
life. Amalgam fillings are most commonly replaced because of cracks in the fillings or because of decay
underneath.
The Mercury Debate
It is an undisputed fact that mercury is toxic and human exposure can result in some very nasty side effects. Much
of the cause and effect health claims cannot be proven, but I feel you should still follow a common sense
approach.
Somehow I just do not feel comfortable storing a material that the EPA has designated a waste disposal hazard. I
cannot throw it in the trash or bury it in the ground.....so we have chosen not to stock it in our office.
We have offered only composite restorations for over a decade now. The composite materials in use today have
come a long way. They have an excellent life expectancy, are strong, and are aesthetically pleasing. Most
materials in use contain glasses, ceramics, and small amounts of metal (so the fillings show up on x-rays). A key
feature of composite plastics is their extremely large molecular size which prevents penetrations into body cells.
But, should you have all your amalgam fillings replaced?
1. Rather than replace all your amalgams at once, I suggest that you replace amalgams as their service life
expires, that is when we see cracks, shrinkage, or detect decay.
2. I recommend that pregnant women delay having amalgam fillings replaced until after they deliver.
3. If you are unhappy with the way your amalgam fillings affect your appearance, or if you have concerns about the
mercury issue, you should discuss the possibility of amalgam replacement with your dentist.
4. We recommend that only 2-3 amalgam fillings be replaced per visit. This is consistent with the
recommendations of many industry experts, and is intended to minimize the per session exposure of mercury to the
patient.
5. If you feel you may have medical issues or allergies relating to mercury, you should discuss it with your
physician. If they feel that amalgam replacement is a recommended course of action, please inform your dentist.
6. We may recommend amalgam replacement to you if there is evidence that a tooth has been weakened by the
expansion and contraction of amalgam fillings. Large fillings may not be appropriate for a composite so we may
recommend other restorative options such as ceramic onlays.
Steps we take to protect your health:
1. A rubber dam is placed over the tooth to isolate it and prevent you from
swallowing any mercury particles. This dam also helps prevent you from breathing
mercury vapors.
2. The amalgam filling is kept cool with water. Mercury vapor pressure doubles with
about every ten degree rise in temperature.
3. High volume evacuator tips are used to suction vapor and particles from your mouth quickly after they are
released.
4. We section the amalgam fillings with a burr before removing them so that they come out in large chunks, rather
than tiny pieces.
5. We ask that you try to breathe through your nose during the removal procedure.
6. After the filings have been removed, we will remove the rubber dam and lavage (rinse) your mouth for about 30
seconds while applying suction.
7. Your protective bib will be replaced before proceeding with restorative work.
8. We immediately dispose of the mercury alloy materials.
9. We recommend that you wash your face thoroughly after your procedure.
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