Tooth filling materials Dental amalgams & alternative materials

6. Conclusion on health effects of dental amalgams and their alternatives on users

• 6.1 What is the scientific evidence linking dental amalgams to health problems?
• 6.2 How safe are dental amalgams containing mercury?
• 6.3 How safe are alternative tooth filling materials?

6.1 What is the scientific evidence linking dental amalgams to health problems?

For many decades there has been a debate about the possibility that mercury-containing amalgam can cause diseases. In spite of many studies and investigations into this claim, there is no scientific evidence that the current use of dental amalgam poses a risk of disease including kidney disease or neurological and psychological effects such as Alzheimer’s, Parkinson Disease or Multiple Sclerosis. No link has been found between the use of amalgam and the development of brain function in children.

Some local adverse effects are occasionally seen with dental amalgam fillings, including allergic reactions. However, these are rare and normally readily managed.

Because of the way alternative materials are regulated in the EU, when regulatory approval is sought for a specific material it is not necessary to provide a design dossier including a risk analysis and therefore the chemical specification does not have to be revealed. As a result, there is limited toxicological data publicly available for these materials.

The relative risks and benefits of using different tooth filling materials should be explained to patients and the public at large. More...

6.2 How safe are dental amalgams containing mercury?

People with amalgam restorations are likely to have higher levels of mercury in their blood and urine than those without. However, these levels are lower than those that cause adverse health effects. Results from epidemiological studies do not support any links between mercury and any of the diseases that have been suggested as being associated with dental amalgam.

Allergic reactions and other local effects are occasionally seen in individuals with amalgam fillings. However, such effects are rare and removing the restoration usually alleviates the symptoms.

The removal of amalgam restorations will expose the patient to relatively high levels of mercury. Therefore it is safer to leave the filling in place unless the patient has an allergic reaction to dental amalgam.

There is no evidence to suggest that pre-existing amalgam restorations pose any risk to the health of pregnant women and children both before and after birth. Nevertheless, as with any other medical intervention, dentists should be cautious when considering the placement or removal of fillings in pregnant women.

The current use of dental amalgam is safe for patients. Dental health is an extremely important component of general health care and the benefits of amalgam to individuals with decayed teeth far outweigh the very low level of risk associated with allergies.

Dental workers may be more exposed to mercury than the general population. However, very few adverse effects are reported and the risk to dental workers has decreased substantially with improvements in the systems used to mix amalgam and in amalgam hygiene practices in general. More...

6.3 How safe are alternative tooth filling materials?

Alternative tooth filling materials are made of a complex mixture of chemicals and there is little information on the toxicity and health effects of these.

Although some components of alternative materials have been shown to cause mutations or be harmful to cells, there is no evidence of any adverse health effects associated with such substances, apart from a very few cases of allergies.

There is thus no evidence that tooth fillings containing these materials cause any neurological disorders or any other diseases. As with any other medical intervention or product, dentists should be cautious when placing restorations in pregnant patients.

Alternative tooth filling materials can cause allergic reactions in dental workers, mainly when they handle some of the resins which form the basis of many products. These contain very small molecules that can pass through gloves and can lead to local skin reactions in some individuals, particularly if they have cuts, abrasions or certain skin conditions.

Alternative tooth filling materials are continually being developed. Information on their composition and potential toxicity is sparse, so caution should be exercised before new variations are introduced into the market.

It is difficult to make direct comparisons between dental amalgam and the alternative materials since they are not used in the same way. Amalgams are very strong, cheap and durable and may remain the material of choice for large restorations in back teeth. Alternative materials look better than amalgams, stick to the surrounding tooth and require the removal of less tooth material. However, teeth restored with alternative materials may be more likely to be affected by new caries between the tooth and the filling and, in some situations, alternative materials may be less durable than amalgams.

Dental health can be ensured by both types of material. All the materials are safe as used and associated with very low rates of local adverse effects with no evidence of general principle, the relative risks and benefits of using dental amalgam or the various alternatives should be explained to patients to help them make informed decisions. It would also be beneficial for the community in general to be better informed of the recognized benefits and risks.

In any case, more experimental, clinical and epidemiological research on alternative materials is required to guarantee patient safety in the future since it is expected that the use of dental amalgam will decrease across the European Union in favour of alternative materials and since data on the toxicity, exposure, and health effects of these alternative materials is lacking. More...