In recent decades there has been much discussion about the safety of mercury amalgam fillings. Unfortunately, the debate has been marred by much misinformation.
Mercury amalgam is the silver-coloured material used to fill cavities. It is made from almost equal parts of liquid mercury and a mixture of metallic powder containing silver, tin, zinc, copper and other metals. The mixture is very durable and cost-effective, especially compared to tooth-coloured resin composites and glass ionomer cement.
The argument goes that mercury vapour is released when fillings are placed and removed, as well as during prolonged chewing. The maladies caused by mercury vapours are the same ones which used to affect milliners, giving rise to the phrase ‘mad as a hatter’ – depression, anxiety, insomnia, headaches, skin allergies and neurological conditions – all of which have been on the rise globally over recent years.
Health authorities are rightly questioning whether the rise of these conditions across the world – including here in London – could be linked to the use of mercury amalgam fillings.
While there is little evidence available to support this, some countries have taken a better-safe-than-sorry approach. Canada and Sweden have both introduced measures to limit the use of mercury in dental applications.
However, mercury amalgam remains the most popular dental filling material globally.
Should we be worried?
The most often cited research on mercury amalgam fillings is a German study published in the Journal of Dental Research in 2008.
It looked at a group of 90 patients with unspecified medical or psychological complaints, splitting them into three groups: Patients who had fillings removed; those whose fillings were removed in conjunction with detoxifying vitamin treatments; and a control group who still had fillings but maintained healthy and active lifestyles.
Prior to removal, the most common health complaints among the 90 subjects were skin rashes, headaches, nervousness, sleeplessness, general tiredness and more frequent attacks of infectious diseases.
Less common, though still reported, were conditions such as allergies, sensory disorders, and cardiovascular, gastrointestinal and urological problems.
At the end of the 12-month study, both groups who’d had fillings removed reported a drop of 3.5 points in the most common complaints. Cause for concern? Not quite. Our third control group also reported a decrease in complaints of an albeit smaller 2.5 points. And symptoms continued to improve for all groups throughout an 18-month follow-up period.
The report’s authors concluded that the improved health of all three groups suggested mercury amalgam was not the culprit, and that any potentially negative effects of mercury would be small enough to counter through good nutrition, exercise and relaxation techniques.
While evidence remains thin on the ground, some health authorities continue to keep an eye on the issue. Notably, the US’ Food and Drug Administration (FDA) which regularly reviews – and approves – the safety of mercury amalgam as a dental filler.
In spite of the scientific consensus, the public may yet take some convincing. Mercury still enjoys something of a bad-boy reputation as a substance to be avoided.
If you still have concerned about the possible ill-health effects of mercury amalgam fillings, you are advised to talk with your dentist or doctor and choose the non-mercury based dental filling materials.