Many people have metal fillings in their mouths, called dental amalgam fillings, which contain 50% mercury, combined with an alloy of other metals. According to The World Health Organisation in 1991 the major exposure to mercury is from dental amalgam in the form of mercury vapour, which is fat-soluble and passes readily through cell membranes and across the blood brain barrier. The mercury transfer to human tissues accumulates with time and may present a health threat. The amount of mercury vapour released is increased when other metals are present in the mouth next to the amalgam fillings. When dissimilar metals are placed in the oral cavity they exert a battery like effect because of the electroconductivity of the saliva. The electrical current causes metal ions to go into solution at a much higher rate, thereby increasing the exposure to mercury vapour solution and mercury ions many fold.
The Department of Health in 1998 in one of their rare statements on mercury advised that exposure to mercury vapour is greater during placement or removal of amalgam. Once the drill touches the filling the temperature increases immediately vaporising the mercury component of the alloy. Although we are all at risk during these procedures the Department only advised pregnant women to avoid such procedures because of the possibility of mercury vapour crossing the placenta.
At Integrated Dentalcare our aim is to protect our patients as well as our dental team from additional exposure to mercury. We would be unhappy to use this material for our families and ourselves and therefore are unwilling to use it for our clients.
It is still a matter of debate within the scientific community whether one should have amalgam fillings removed if there is no dental problem. We as dentists have a duty of care to our patients to present all the arguments for and against mercury fillings and we are concerned that patients anticipating resolution from specific conditions and symptoms are not mislead or their hopes allowed to be raised to unrealistic levels. Our personal belief is that there are many suitable alternatives to dental amalgam, which also appear more natural.
What can we use as an alternative to mercury fillings?
The newer materials available on the market today are referred to as bonded resin ceramics, composite resins or just composites. These materials have been subjected to numerous clinical trials all over the world to determine whether they are biocompatible and safe to use in the human body. Our dentists have a combined experience of three decades with this material. As such we have a very strict protocol on placement of material resulting with a very high success rate. Occasionally there are anecdotes of people suffering from sensitivity or pain after having composite fillings or the fillings not lasting very long. Of course there is a difference in the qualities of different composite materials. This can lead to some products not lasting as long or appearing to discolour very quickly. As with everything else, the composite materials used at Integrated Dentalcare are of a premium quality. To increase their life expectancy the latest generation of composites contain ceramic nano-particles resulting in exhibited wear resistance similar to natural teeth. Are composite materials inert? Composite materials have been found to have oestrogen-mimicking properties. Unfortunately nothing in dentistry or medicine is 100% biocompatible. Recently, however, with the advent of CAD CAM milling technology and Zirconia, we have found a truly biocompatible material. However, unlike composite which can be very conservatively used to repair the damage caused by infection – a process enhanced manifold by the introduction of the water laser – Zirconia requires some destruction of the healthy tooth structure to be used (much like amalgam).
Safe Removal of Mercury Fillings
Protection of the patient from additional exposure to mercury is of the utmost concern during the removal of mercury fillings. This is especially true of the mercury toxic patient. The goal of this procedure is to minimise any additional exposure of the patient, ourselves, or staff to mercury.
Before Removal of the Mercury FillingAfter Replacing Mercury Filling with a Ceramic Filling
Therefore we have very strict protocols to follow when we are carrying out this treatment.
Briefly, these include the following precautions:
- Isolation of the treatment area, usually by a technique known as ‘rubber dam’, to minimise exposure to debris in the mouth
- Use of high speed, distilled water-cooled instruments
- Use of high speed powerful suction system
- The option to use a nosepiece, to provide an alternative air source out of the immediate area to protect against nose inhalation of mercury vapour
- The option to use dampened gauze eye patches to keep flying particles or vapour out of the eyes
- Use of general protective coverings
- When drilling, the filling is sectioned into chunks and elevated where possible
- Nutritional support considerations, to support the immune system
- Restoration of remaining tooth structure with a premium quality resin material
- Patients should wear clothes covering as much skin as possible