However, unless the dental team are prepared to dress in space suit type protective clothing while filling and drilling to remove amalgam, mercury vapour can transfer into the atmosphere of the surgery and this can then be inhaled. As mercury is only slowly excreted from the body the burden of mercury is likely to increase with exposure, the longer the exposure the more mercury is found in the body. Intervention to minimise the toxic effects of mercury and other free radical inducers is feasible for both the dental team and patients. Probably the most effective protective agent against the hazards of mercury poisoning is the element selenium. This has the advantage in that it can combine with mercury to reduce the bioavailability of the mercury, possibly by competing with it for critical low molecular weight proteins used in metal transport.
Selenium is a vital component of the metallo-protein enzyme glutathione peroxidase.
This is a major component in the body's free radical defence system. The availability of selenium is the limiting factor in the production of glutathione peroxidase, as modern day diets tend to be deficient in selenium its addition in the form of a nutritional supplement is the surest way of ensuring that adequate amounts are available for detoxification purposes. Other protective agents that protect against free radical activity are the various anti-oxidant vitamins. As vitamin A can be toxic if taken in excess the preferred form of this vitamin is -carotene. Some dental teams already take nutritional supplements of selenium and anti-oxidant vitamins and have noticed significant improvement in their health, particularly in their increased ability to undertake procedures involving repeated fine movements.