Health Center » Healthy Dentistry

The Third Amalgam War
Part 1
By: Stephen R. Goldberg, D.D.S., C.C.N.

 

 The Third Amalgam War is in full swing at the present time. For almost two centuries there have been controversies over the effectiveness as well as the safety of silver amalgam (mercury) fillings. The first recorded use of the mixture of mercury (quick silver) and silver powder for filling cavities in teeth was in Paris around 1820. The soft amalgamation hardened in a few minutes, and, when it was placed in a tooth, had a very good retention. It didn’t fall out because as the mixture hardened, it expanded and was wedged against the parallel walls of the cavity within the tooth. It expanded to such a degree, in fact, that many of the filled teeth cracked or split in half after a while. Cracked teeth hurt! Don’t they? Especially if the nerve becomes exposed at the cleavage plane. As a result, amalgam fillings were soon abandoned after these initial attempts. Unfortunately, this abandonment lasted for only a few years.

 

In 1833, two opportunists from England, the Crawcour brothers, brought amalgam fillings to America. They opened their office in New York and advertised their cheap, easily placed "new" filling containing a mixture of silver and mercury. They called them "silver" fillings, because silver sounds like jewelry. The Crawcour brothers were ruthless competitors and were soon considered a threat to American dentists. Amalgams were denounced not only as an inferior filling material, but also as a harmful, toxic mixture causing periodontal (gum) disease; erethismusmercurialis (mercury poisoning); and fractured, painful teeth. The Crawcour brothers were eventually expelled from America. Soon after, many societies of dental surgeons in America unanimously banned the use of dental amalgam. In fact, in 1848, several dentists were suspended from the society in New York for malpractice because they were using amalgam. Thus ended the First Amalgam War.

 

For the next half century, the use of amalgams was abandoned in the United States. But then, near the turn of the twentieth century, experiments were again performed in an effort to improve these fillings. It was noticed that when different powdered metals were added to the silver filings (powder), the expansion rate was altered. When these new metal alloy mixtures were triturated with mercury, the "silver" fillings no longer were cracking teeth. The metal element that was key in controlling the expansion rate was tin. As a result of this finding, dentists agreed that the perfection of dental amalgam had been obtained. Unfortunately most of these dentists were showing their true colors. They were indeed only micro-mechanics and not doctors. They were mainly interested in making more easy money with these quick, simply placed fillings and either ignored or forgot that mercury is a harmful, deadly poison. The anti-amalgamists lost the Second Amalgam War.

 

In 1926, a German chemist and pharmacologist, Alfred Stock, documented in detail his own personal experiences with mercury toxicity. He was chronically exposed to and was inhaling the mercury vapors in his laboratory as well as the mercury vapors from his fillings. He had extreme fatigue and could not concentrate and work for a sustained period of time. After he moved to a non-mercury laboratory and had his amalgam fillings removed, he recovered from his severe mercury intoxication. Unfortunately, Stock's efforts were sidetracked and forgotten when the Second World War began.

 

It was not until 1981 that this mercury issue was reopened. Thus began the Third Amalgam War. This time, Sweden was at the forefront of the battle. A brilliant neurobiologist, Mats Hansen, at the Institute of Zoo physiology at the University in Lind, Sweden, sent a letter to the National Board of Health of Sweden demanding an unprejudiced evaluation of the hazards of dental amalgam.

 

Since the notion that dental mercury fillings are toxic is still very controversial in numerous circles, I will cite a few conclusive studies in peer-review medical and dental journals. The first was printed in 1979 in Lancet, the most prestigious peer-review medical journal in Great Britain. The title was "Chewing releases mercury from fillings" and it was written by Gay, Cox and Reinhardt. Then in 1984 in the American Journal of Dental Research, Abraham, Svare and Frank studied the effect of dental amalgam restorations on blood mercury levels. They found that the blood mercury concentrations were positively correlated with the number and surface area of amalgam restorations and were significantly lower in the group without dental fillings.
It was not until 1986 that, in Lakartidningen, a Swedish medical journal, that Frieberg, Kullman, Lind and Nylander described a study relating mercury in the central nervous system to dental amalgams. Eighteen cadaver brain species were analyzed for organic and inorganic mercury. The brain specimen from the cadavers with amalgam fillings had about three times the mercury levels than the brain specimen from cadavers without amalgam fillings. The amount of mercury in the brain samples was directly related to the number of amalgam fillings in the individual.

 

The really impressive cadaver study was reported in 1987 in the Journal of the California Dental Association by Eggleston, et al., entitled "Correlation of dental amalgam with mercury in brain tissue." In this study, 77 cadavers were analyzed for total mercury content. Data from this project demonstrated a positive correlation between the number of occlusal surfaces of dental amalgam and mercury levels in the brain. Three months later the same study was published in an even more prestigious periodical, the Journal of Prosthetic Dentistry.
When I was studying dentistry, I occasionally heard professors and other dentist’s mention that of all professionals, dentists have the highest suicide rate. I have recently become aware of two dentists that I knew, a former classmate and a prospective associate, who committed suicide. One symptom of mercury poisoning is depression. Maybe the high suicide relate is correlated to a higher than average amount of mercury accumulation in the brain of dentists using mercury fillings. In fact, in 1986, one year before the Eggleston, Nylander et al., publication, Lancet had published a research study by Nulander of Sweden. Nylander had analyzed seven cadavers. Three of them had been dentists. He found very large amounts of mercury in their pituitary glands. The non-dentist cadavers had much less in their pituitary glands and brains. It was surmised that the mercury from the vapor of dental amalgams being placed in teeth may have been absorbed by the nasal mucosa and directly transported to the cranial cavity and the pituitary gland.

 

Although many organs have also been shown to accumulate mercury to a greater extent in someone with more fillings, the brain studies are most crucial and important. These studies culminated with the work of Murray Vimy, D.D.S., in 1990. Vimy conducted his research at the University of Calgary in Alberta, Canada, and had his double-blind study published in one of the most revered medical peer-review journals in the world, the American Journal of Physiology. Vimy drilled and filled the molars of half of the ewes in his sampling with silver amalgam fillings containing radioactively tagged mercury. The other half of the ewes in his study had no fillings of any kind placed in their teeth. When the fetuses of these ewes with fillings were analyzed, he discovered that they had the same radioactively tagged mercury in their brain cells as was present in the parent ewe's fillings. The control group of fetuses had no mercury in their brain cells at all! What may be concluded from this brilliant experiment? #1 Mercury is released from silver-mercury fillings. #2 Mercury passes through the placental barrier. #3 Mercury in our blood passes the blood-brain barrier to enter our brain cells.

 

This impressive, well-planned study ruled out the possible influence of environmental sources of mercury by using radioactively tagged mercury. Many of the previous experiments indicated the release of mercury from amalgams and its accumulation in the brain, kidney, pituitary and other organs, and the conduction of mercury through the circulatory system and placental barrier. However, this was the first experiment to incorporate all of these factors in one.

 

Three years prior to the results of Vimy's study, Sweden banned the use of amalgams in pregnant women.
In Part II, I will cover the recent developments and legal battles of the anti-amalgamists. There may be light at the end of the tunnel. If this third war is won, there may never be a Fourth Amalgam War.

 

 

 

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