This week we feature an article written to support a nationwide ban on the use of amalgam fillings in dentistry. It’s not that womenz.co.nz necessarily endorses unreservedly this campaign; rather, we’re including it, and talking about it here, to promote thoughtful decision-making. Even a cursory surf of the Internet will alert you to the ferocity of the debate, one that has been raging off and on for 150 years.

The controversy is over the potential adverse effects arising from the inhalation and absorption of mercury vapour from the amalgam used in fillings. The science consistently confirms that mercury is absorbed in this way, but the World Health Organisation (WHO), the US Public Health Service and the European Commission conclude that there’s no relevant and definitive evidence to demonstrate a causal link between dental amalgam and adverse health effects, except in the case of rare allergic reactions.

In an effort to get to the bottom of what the research is really saying, the US Government commissioned an examination of the peer-reviewed studies from 1996 to 2003. It tried to ensure a fresh, unbiased approach by assembling a panel of scientists from a variety of specialties, all outside of the dental research community, but even so, the accusations of bias, incompetence and undue influence of vested interests have continued unabated.

The review of the studies came up with conclusions such as: insufficient evidence to support a correlation between dental amalgam exposure and kidney or cognitive dysfunction, neurodegenerative disease (Alzheimer’s and Parkinson’s diseases), or autoimmune disease, including multiple sclerosis; various non-specific complaints have not been shown to be due to increased mercury release from dental amalgam. Possibly the most important conclusion was that there are many gaps in the research which, if addressed, could settle the controversy once and for all!

It seems to me that, as ordinary dentist-goers, we need to adopt much the same approach as jurors in a criminal trial: weigh up the evidence in total and decide how credible the various people and organisations are who are making the claims and counter-claims. As in a criminal trial, the absence of irrefutable scientific proof doesn’t mean that the accused is innocent; it just means they probably won’t be convicted. We jurors also need to take into account the ‘circumstantial evidence’ of the thousands of cases of recovery or significant improvement in chronic health conditions after amalgam replacement.

We need to make a call on how serious we consider the risk to be from the mercury in amalgam, given that there are risks everywhere in life, some easy, some difficult and some impossible to avoid. Here are some questions to decide:

·        What to do, if anything, about one’s own ‘metal mouth’ 

·        If deciding to get the mercury levels checked, what test to undertake (there are several methods available and, of course, controversy over which is the best)

·        What dental treatment to have from now on and also what to obtain for one’s children

·        How much weight to place on the advice of dentists who stand to benefit financially from replacing amalgam fillings with an alternative

·        Whether one feels strongly enough about this to support a ban on amalgam fillings in the future.

To me this seems all too hard, but I need to remind myself that the ‘ignore it and do nothing’ option is also a decision in itself.