Letter to ADA with unconditional offer to present evidence on amalgams
3 February, 1998
The Federal Executive,
Australian Dental Association,
75 Lithgow Street,
I am writing because of my deep concern about ADA policy on dental amalgams. My concerns lie in several areas which I would like to detail for your consideration.
I am concerned that the ADA does not listen to other points of view, only the ones it has selected. This closes off the possibility of a change in policy unless the designated advisers are always aware of and continuously evaluating new research. This has clearly not been the case.
I accept the ADA assertion that it is not in the position to make policy and that it relies on the view of other, more expert, bodies. My concern is that the ADA has abrogated its responsibility in this matter by failing to adequately assess the quantity and quality of the advice it has been given and whose advice it chooses to listen to. There has been a demonstrable inadequacy in the advice of a number of bodies and people who the ADA has chosen to advise it. I offer the following in support of my observation.
Royal Australian College of Physicians. I contacted the RACP and asked for a copy of their report to the ADA in which they stated that amalgams were safe. I was told that no report had been prepared, so none was available but that they supported the ADA position and the NHMRC position. I then asked for a list of the experts consulted in this review process and was told that it was not available to me. In summary, RACP has no written report, no written literature review and no names of the experts consulted. We do not know how they arrived at their position, what literature they reviewed and who reviewed it. My assessment of their credibility in this matter is that it is non-existent.
NHMRC. The fiasco with the NHMRC advice is known to you. In summary, the only document from the NHMRC on this issue was the brochure which was withdrawn in August last year. NHMRC have confirmed in writing that no other document exists, that the only study thought relevant at the time was the one cited in the brochure, meaning there was no extensive literature review, no written report to refer back to, only the brochure. The brochure stated four conclusion citing the Ahlqwist study. The study had nothing at all to do with the four conclusions which is why Professor Leeder withdrew it from distribution, in his own words....the brochure badly misquotes the study. NHMRC now claim that their policy is unchanged and that only the policy statement has been withdrawn. This statement is in conflict with written advice I have received from Professor Leeder and it is noteworthy that several requests since then have failed to elicit any written response documenting current NHMRC policy. Regardless of the interpretation of Professor Leeders advice it is clear that NHMRC policy was framed on a very flimsy foundation. Credibility of NHMRC on this issue has to be considered to be very poor.
Professor Michael Moore. I wrote to Professor Moore and asked for a copy of his report to the ADA. He had not written one. I then wrote and asked for a copy of his CV and publication list. After 15 months and many letters I received one and found that, to the best of my ability to discern, there was not one article which Professor Moore had published which looked at mercury from dental amalgams. I have no doubt that the credibility of Professor Moore is high in his area of expertise. He has not, however, demonstrated any expertise in this specific area, so his credibility in this subject, particularly in the absence of any indication as to how he arrived at his conclusions, can legitimately be questioned.
Professor John Dwyer. I could not find, in Prof Dwyers publication list, anything showing publication in any scientific journal on the subject of mercury from dental amalgams. As with Professor Moore, I have no doubt about Professor Dwyers credibility in his area of demonstrated expertise but such expertise has not been demonstrated in this issue. Credibility can be legitimately questioned.
I have no objection to the ADA designating certain groups or individuals as its advisers. The ADA cannot, however, walk away from the responsibility of critically evaluating the advice it receives from such people. The ADA must ask these people and groups to justify their conclusions with written, fully referenced reports.
It is appropriate that the ADA refer to reviews undertaken by other bodies. As with advisers it is also important to assess the reviews critically. One such review often cited is the USA Health and Human Services Jan 1993 report. It was asserted in the April 95 ADA News Bulletin, page 5, that this report concluded that there was no evidence to support the discontinuation of amalgam as a safe and effective filling material. A closer reading of the report itself would have revealed many statements in conflict with the official conclusion. To list just a few.
"This report is not intended to serve as the authoritative source on dental amalgam safety, but rather as a planning tool to assist policy makers in deciding on appropriate risk management actions."
"In the absence of adequate human studies, the subcommittee on risk assessment could not conclude with certainty whether or not the mercury in amalgam might pose a public health risk".
" Available data are not sufficient to indicate that health hazards can be identified in non-occupationally exposed persons. Health hazards, however, cannot be dismissed."
"The margin of safety may, however, be lower because body burdens of mercury are already high as a result of exposure to other sources: some persons may perhaps respond adversely to the incremental exposure to mercury derived from dental amalgams."
"The potential for effects at levels of exposure produced by dental amalgam restorations has not been adequately studied."
"The available research evidence is not specific enough or strong enough to make sound pronouncements about human health risks from dental amalgam."
There are other similar statements. The above statements from the various work groups are clearly much more cautious than the conclusion would suggest. I hope this shows the dangers in just reading a conclusion without reading the body of the report. This is why the ADA must listen to dissenters and not label them as fringe or conspiracy theorists.
I am concerned at the concerted efforts to put any pro-amalgam view in the most favourable light and any anti-amalgam view in an unfavourable light. Facts are facts. Who it is who says something is irrelevant. The evidence must stand or fall on its own. The profession has had almost no exposure to the research casting doubts on amalgams. The ADA must make efforts to disseminate ALL legitimate research in this area, whether pro or anti amalgam, so that the profession is fully informed. Currently, ignorance of all the scientific research is the key inhibitor in the professions attempts to deal with this issue. Again, this is why the ADA must listen to dissenters and not label them as fringe or conspiracy theorists.
I am concerned that nothing is being done to alert the profession to recognise symptoms of mercury toxicity. The profession has no training in toxicology and has, for too long, focussed on the engineering aspects of dental material with no attention to possible toxic effects over the long term. It is entirely predictable that dentists do not see any evidence of mercury toxicity. It is also true to say that the majority of dentists are still not confident or totally competent in the use of posterior composite resins, further inhibiting them from considering stopping the use of amalgams in their own practice. The ADA must encourage quicker and more thorough re-education in this area.
I am concerned how the ADA has adopted a very conservative and extreme position. Just as it is nonsense for anyone to claim that all health problems stem from the use of amalgams, so it is equally nonsensical to assert that there is no evidence at all that amalgams are harmful. The two studies most often cited in support of amalgam safety are the Ahlqwist study and the Nun study. Both are fatally flawed because they misrepresent the body burden of mercury by counting only the number of amalgams with no account being taken of the bodys long term exposure to mercury from amalgam filled teeth which have subsequently been lost. This failing shows a basic misunderstanding of the problem which is one of long term accumulation of mercury from amalgams which may or may not still be present. There is only one study of which I am aware which had a control group of people matched for sex and age, which compared a group with amalgams with a group who had never had amalgams, and thus no exposure to mercury from amalgams. That study found significant differences between the two, concluding that the amalgam group reported 45% more health disorders. The same study also reported on 86 subjects who had their amalgams replaced. Results showed that after 10 months, 70% of previous health problems in this group had improved or disappeared. (Siblerud RL, Relationship between mercury from dental amalgam and health. Toxic Substances Journal 1990 10:425-444 )
I appreciate the ADAs difficulties in this matter. May I suggest some avenues for your consideration. The ADA can choose who it listens to. May I suggest the ADA consider listening to the German Health Department which directed its profession to not use amalgam fillings in pregnant women or young children. May I also suggest the ADA consider listening to the Canadian Health Department whose recommendations, as a result of the Richardson report, led the Canadian Dental Association to recommend caution with patients who had kidney problems or neurological problems. Both these bodies are legitimate, authoritative and credible. The ADA can choose to adopt an approach of caution and in the interests of preventive medicine make similar recommendations to its members. It does not have to recant the view that there is no evidence of harm from amalgams but can instead state that it is adopting a position of prudent caution based on recent recommendations of two credible overseas institutions. At the same time it can call for further research. This would be a defensible and low risk move, restoring much credibility with the public. I give you an undertaking that neither I nor ASOMAT would use such a move by the ADA to score points or to embarrass the ADA. Secondly, may I suggest that the ADA consider inviting someone such as Dr. Murray Vimy to give the ADA council, as well as the academics, a full briefing of the anti-amalgam research. If you would prefer, I , and/or Dr. Gammal, would be happy to give an initial briefing to show the ADA the extent of the research before ADA invited Dr. Vimy. Again, I give you an undertaking that neither I nor ASOMAT would use such a decision to embarrass the ADA. Thirdly, please consider a debate on this issue so that both points of view can be canvassed by the members. A debate in each capital city, perhaps an extensive report in the News Bulletin. Fourthly, please keep the lines of communication open to the anti-amalgam dissenters. Do not denigrate them and do not treat what they say with condescension or sarcasm.
This issue is very important to our profession. It represents a paradigm shift in our thinking about what we do as dentists. It is very challenging and it therefore evokes strong emotional reactions. We have an opportunity to move from being mechanically oriented to a position of more fully integrating a biological approach to our patients. This can only make our profession more satisfying, more respected and more effective.
I welcome your comments,
Letter to ADA
ADA reply to above letter
09 February 1998
Dr Roman Lohyn
8th Floor, Kurrajong House
175 Collins Street
MELBOURNE VIC 3000
Dear Dr Lohyn,
At its meeting on 5/6 February last, Federal Executive considered several matters arising from your recent telephone conversation with the Executive Director, Dr Butler, and your letter of 3 February 1998.
It is clear that your concerns are broadly that you consider that the ADA is not prepared to listen to alternative points of view, which you maintain is based on scientific research. Furthermore, Dr Butler reports that you wished access to the pages of the News Bulletin to present these reports and a viewpoint other than that which has been expressed by ADA statements You have also suggested that the ADA might like to arrange for Dr Murray Vimy to address ADA officers or expert Committees.
Your requests are declined, I have previously instructed Dr Butler that he was not to spend any more time in continuing this vexatious correspondence and have today re-issued this instruction to him. We do not wish to play games, Dr Lohyn, the ADA will take its advice on health matters from recognised and accredited medical specialists and not from self-taught instant experts. You may most confidently assume that the postage stamp on your next letter to us will be a very poor investment!
Reply from ADA