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
amalgam can cause
diseases. In spite of many studies and investigations into this
claim, there is no scientific evidence that the current use of
poses a risk of disease including kidney disease or
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
Some local adverse effects are occasionally seen with
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
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
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
There is no evidence to suggest that pre-existing
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
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.
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
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
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.