The health threat from mercury poisoning has long been an issue in dentistry due to the inclusion of mercury in silver amalgam fillings. For many years there was little that could be done about it, because there were no viable alternative filling materials available. In more recent years, however, the bonded composite resins have continuously been improved and strengthened to the point where they are today a very viable option to the use of dental amalgam fillings, even in the back chewing teeth.
If you have new cavities or old silver fillings that are in need of replacement, ask your dentist about tooth colored fillings. These bonded composite resins can be done in one visit like the old amalgam fillings, or in the case of more extensive tooth structure damage, in two visits as an inlay or onlay made in the laboratory.
Amalgams vs Composites
When considering what you want for your teeth, consider the following points:
* Amalgams cost less generally, but also look cheaper. Amalgams darken with age and end up as black fillings. Composites are tooth colored and the newer generations hold their color very well.
* Amalgams contain mercury, which is a very toxic heavy metal. The degree to which mercury is released from amalgam fillings has long been in dispute, but there is no question that it is released and absorbed into the system. It can not easily be removed from the body once absorbed, so it has a cummulative affect. There is some occurance of allergy to dental composite resins, but this is quite rare and usually self limiting as well.
* In order to place an amalgam filling, quite a bit more tooth structure must be removed, beyond the actual decay in the case of small new cavities, than with the bonded composites.
* Amalgam tends to expand with age, pushing outward on the tooth from within the cavity preparation. This leads to many teeth cracking and breaking off parts of the teeth. When properly handled, composite resins tend to hold the tooth together because of the bonding.
* Amalgam restorations are weakest at the margin between filling and tooth where they are thinnest. It is here that they chip and wear and begin to allow re-decay underneath. Composites are actually strongest at the bond junction between tooth and filling. There tends to be much less re-decay at this junction than with traditional amalgam.
* Amalgam conducts heat readily leading to many teeth having post-operative sensitivity. With properly placed composite resins, we experience much less post-operative sensitivity than in the past.
It is important that you develop a good raport with your dentist and discuss with them the materials planned for use in your teeth. Research your options and ask your dentist about your findings.
