Critique and comments to the Report from the EU Ad Hoc Working Group on Dental Amalgam.


1. Membership of the working group.

After a check of the members in the work group it is conspicuous that not one single dentist or doctor is represented who has clinical experience in the treatment of patients who have an apparent and clinically established mercury poisening.

The group is exclusively composed of health authority representatives in certain EU countries, dental colleges, dental associations, and manufacturers and distributers of amalgam products.

Almost all of these members are known to have made statements in favour of the continued use of amalgam, or have obvious economic interests or prestige at stake in a report with a conclusion in favour of amalgam.

Introduction s. 11

The working group writes: "It must be emphasised that this report is not a scientific investigation or treatise on the safety of dental amalgam in humans, but is a report based on the available scientific evidence".

It is evident for the expert with an empirical knowledge of amalgam and its toxicity plus alternatives, that this report clearly does not live op to its goal of determining the risks involved in the use of amalgam.

The report is characteristic of other similar reports in that it is clearly one-sided and is an attempt to justify the continued use of amalgam. As in other reports there is a widespread manipulation of investigative results with misleading information to follow.

The report is wanting and in many fields erroneous both in facts and conclusions.

Important scientific investigations, clinical observations and empirical evidence both contemporary and over the last 150 years which very clearly indicate a considerable health risk from the use of amalgam are circumvented or disregarded.

For laymen such a report gives the impression of being an authoritative review that you should be able to trust. These days many people are environmentally aware. For them it is quite logical that as mercury is so dangerous in the environment and therefore subject to control it is quite wrong and irresponsible to use in dentistry. In addition, people who have composite fillings have long since discovered that these last longer than amalgam and that their gums have ceased bleeding. An increasing number of people who have had their amalgam fillings replaced by composite ones become convinced that they have not been insentitive to their amalgam fillings.

Since the working group has not included all the facts in the report, it cannot give a fair or reasonable evaluation of the risks.

From a clinical dentistry point of view, it has long been seen that amalgam is a poor material for fillings in all ways save its ease and economic in use.

Composites have been developed which have proved their value and reliability, in addition to being found biologically compatible in tests, without causing adverse effects on teeth, oral cavity or the body as a whole.

I fully endorse the Norwegian criticism of the report, however I do have the following supplementary comments to certain points.

I will concentrate on those issues in the report in which I consider I have substantial insight and experience. On the basis of over 41 years as a practicing dentist and 15 years of experience with patients who have been convinced of the poisonous nature of their amalgam fillings, I regard myself qualified to comment on these issues. (Appendix A)

5.2. Mercury, its release from dental amalgam and fate.

In the report on release of mercury from amalgam fillings it is not mentioned that the same is shown to be the case for the four metals tin, silver, zinc and copper, all of which have a significant toxic effect on the bodily organs and their function. The evaluation of the risks are based upon the sum of all the toxic influences, it is therefor insufficient to examine the addition of mercury alone.

It is mentioned on page 22, "that Strietzel and Viohl (1992) concluded: "that mercurial release from gamma 2 free amalgams under stringent experimental conditions is very low, sometimes under the sensitivity limits of the analytical method used and at all times under WHO's safety thresholds"".

This is not in agreement with the results found on the measurements of mercury vapour in the oral cavity for patients with amalgam fillings and my own study in J. Orthomol. Med. Vol 11 No. 2 p. 87-94 1996, in which it is shown that individuals with dental amalgam fillings who exhibit symptoms typical of chronic mercury poisoning, all have mercury vapour concentrations in their oral cavity far higher than acceptable levels and on average, higher than the maximum permitted levels for industrial environments.

The results indicate that the presence of symptoms is not solely dependent on the size of the mercury dose. (Appendix B)

It is "forgotten" to mention that since the end of the seventies the use of "high copper amalgam" with up to 12% copper has been the rule in Scandinavia.

Brune and colleagues at the Northern Institute for Odontolgical Material testing (NIOM) established already in 1984 that this amalgam released aprox. 50 times as much mercury as previous amalgams.

German investigations in Tübingen with saliva samples from 20,000 participants showed, that even the amalgam in use in Germany release larger quantities of mercury. The result of the study shows:

1. The mercury concentrations in saliva depends upon the number of amalgam fillings.

2. 43% of the participants had a mercury exposure which was often several times higher than the highest daily dose recommended by WHO.

6. Biocompatibility of alternatives to dental amalgam

6.1 Composite resins

The working group writes: "Compared with dental amalgam the chemistry of these tooth coloured resins is complicated as there are at least 40 substances known which could be used. These are mostly organic chemicals and include liquid dimethacrylate monomers, initiators, accelerators, ultra violet absorbers, diluens, inorganic fillers and coupling agents. Any composite resin product comprises a variety of these different categories".

This is quite true, however there are resin materials on the market, where the manufacturer has taken into consideration individual elements, so that only chemicals and substances are used which are biologically amicable.

These substances do not for example contain oestragen related chemicals or metals such as BisGMA or aluminium.

I know of one producer, who I have used for some years, who has documented scientific tests of these substances' effects on living tissues and cells. These tests are done on Cytotoxicity - fibroblast Cell Cultures - human blood hemolysis reactivity - Systemic injections toxicity reactivity - Intracutaneous reactivity - intramuscular implantation study - tissue toxicity reactivity - Eye irritation test - The mucous membrane irritation implant reactivity, and all test results were zero, none reactive. (Appendix C)

It is therefore unnecessary to speak of reactions regarding composites, if the manufacturer meets the demands of the product, which one naturally must insist upon today.

The report group writes, that composites shrink and are therefore susceptible to bacterial growth under the fillings causing breakdown of the tooth. In addition it is stated that composites are not durable under masticatory pressures, and that they are more subject to corrosion than amalgam. It is also claimed that composites are more prone til coating than amalgams.

All of this is out of date and is incorrect when considering newer types of composites of polycarbonates.

Of course there are non-cytotoxic adhesives which do not harm the pulpa.

The working group states that amalgam is shown to be superior to composites in durability studies by Quist (1990), and that on average amalgam fillings last twice as long as composites.

A long term extensive investigation by El-mowafy from 1994 shows precisely the opposite, in that composite fillings are far more durable than those of amalgam, as composite fillings last on average 15 years.

This survey encompasses also older types of composites, so in a number of years we will see that, which patients have already experienced, that composites last longer and surely later will show to last a lifetime.

7.6 The benefits of dental amalgam

The working group compares the advantages of using amalgam with the risk of side effects.

The advantages with amalgam are exaggerated and the risk is played down. The conclusion is therefore that generally it is best to continue to use amalgam.

As previously stated amalgam has very few advantages: it is easy and cheap to use.

The following scientific clinical investigations and experience show that plastic composites are stronger and are to be prefered instead of the traditionally used amalgam.

Article in the american Dentists association's magasine JADA vol 117 okt. 88.:

"It has been found that edge fractures occur twice as often with amalgam fillings, in comparison to comparable fillings of plastic composites. After two years, composite fillings had far fewer flaws on the edges than amalgam fillings".

At the dentistry college in Nijmegen, Holland several research studies comparing composite material's durability with amalgam were already done in 1989. This study comparing the durability of composite material with amalgam concluded that: "The material amalgam causes many flaws in fillings, whereas composite material does not effect the incidence of flaws. After 5 years 84% of the amalgam fillings and 89% of the composite fillings were functional".

Another study at the dentistry college in Nijmegen which compared amalgam and composite fillings, showed for instance that corrosion on the chewing facets was less for composite fillings than for amalgam fillings.

A clinical study of a composite material "Heliomolar", which was used extensively for molar teeth some years ago, showed that "the material also after three years was completely satisfactory as a filling material in molar teeth".

Studies show that aprox. 20% of amalgam fillings are broken after 5 years and 50% after 10 years. A long term study of 899 composite fillings durability showed that only 9.2% of composite fillings were broken after 5 years. It was concluded: "that with so few flaws, it looks as though composite materials for molar teeth are splendid for long term use".

Professor Felix Lutz from the School of Dentistry at the University of Zürich does not agree in our health authority's stance that composite fillings only last half as long as amalgam. He says: "It depends on good technique, if one does not master it, the result will be poor. It can be objectively, empirically demonstrated, that these products are better than amalgam with regard to durability". Prof. Lutz continues: "It is unfortunately easy to say that nothing can be found which is better than amalgam, and then continue in one's way".

At the School of Dentistry in Zürich work with amalgam is no longer taught.

"Finally the end of amalgam", is written in the aknowledged dental periodical "Quintessence International" Vol. 26 no 3/95. The Editor in Chief writes among other things: "The amalgam experiment is over. Composite materials are now so strong that they are more durable than amalgam. If amalgam continues to be used, it is a sign of laziness and habit or tradition, together with fear for change and in opposition to the dentists responsibility towards his patients!"

My own clinical experience during the last 15 - 20 years, with thousands of composite fillings, show quite clearly, that composite fillings, in addition to having many other advantages, are more durable, also for patients with a hard bite. It is clearly evident, going through one of my patients' journal, which shows my treatments over a 10 year period, that the amalgam fillings the patient broke and which were replaced with composite fillings, lasted much longer.

A questionaire in which 601 patients expressed their opinion on the use of amalgam and composites in dentistry showed that: to the question "Do you prefer composite fillings in molar teeth instead of amalgam", answered 95% positively -5% not sure. 32% of all those asked had haft composite fillings in molar teeth for more than eight years. Of these 149 patients answered 147, that they prefered composite in place of amalgam for cosmetic reasons and because they had experienced for themselves that they lasted longer!

I refer to the conclusion in my article "Metal used in dentristry, good or bad?" Internet address:

"Though metals are of great usefulness, we must recognize that there are many good arguments for reducing or discontinuing our use of them.

When one reviews the literature concerning metals and the injuries, which have been confirmed, they can cause on teeth and the environment, as well as the whole organism, in the form of chronic toxicity and electrogalvanic lesions, then it is obvious, that dentistry should be using non-metallic biocompatibles and of course non-toxic materials.

According to dental textbooks, it is malpractice to place several different metals in the mouth at the same time. Unfortunately, it appears as though individual dentists have not been complying with these guidelines.

There are many advantages with changing to composites and polycarbonates. They do not form battery-like elements creating galvanic currents in tissues. In relation to metals and porcelains they are more biocompatible and practical as well as being more durable, especially when they have been reinforced with fiberglass tissue. In addition, the materials in crowns and bridges are much cheaper and easier to use.

It is important in this connection to emphasize, that future patients will almost certainly make greater demands regarding the cosmetic appearance of dental materials, biocompatibility and durability.

Greater and greater environmental concern on the part of the population will result in a refusal on the part of patients to have heavy metals or toxic chemicals in their teeth or jaws. The increasing number of allergic patients will also mean that materials, which can cause toxicity or allergy, will be used less and less in dental care."

Closing remarks.

The working group's report is so erronous, misleading and full of incorrect information that unless it is followed up with a veracious and fair critique with corrections, it will do more harm than good.

It is utterly disheartening, that for so many years from both the consumer and the dentists side, it has been accepted that there is no biological control whatsoever with dental materials. Only a very few substances such as arsenic have been prohibited.

It is apparently allowed to make use of all kinds of materials, chemical compounds, metals and heavy metals, although the Danish law requires the dentist, "to seek to use the least damaging or least toxic substances, if it is possible".

demand. This means to say that 100% of the contents should be declared in much the same way that it is mandatory for foods.

All dental materials should in addition to being mechanically applicable also be biologically tested (biocompatible).

The possibility for individual serum tests for specially ill or extra sensitive patients, must also be made a requirement the consumer and the dentist can demand.

It must be remembered, that dental material which is used to fill cavities in teeth is by definition to be regarded as an implantation, "a material which is placed in an unnatural cavity in a living tissue". Materials which are used in these cavities should comply with the most stringent requirements which are laid down for all other implants.


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Tandlæge Henrik Lichtenberg

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