A filling is an artificial material used to replace parts of the tooth that have been damaged by tooth decay or have fractured.
The treatment involves removing all the decay and sealing the hole in the tooth with materials to protect the remaining tooth from further decay, and to allow it to function normally.
There are various materials used to restore teeth including tooth-coloured dental fillings such as composite resins and glass ionomer cements, or metallic (amalgam) fillings.
Replacing amalgam fillings
Amalgam (silver fillings) have been replaced with other methods of restoring a tooth for many reasons. One of the main reasons is because of the nature of amalgam, it may expand causing the filled tooth to crack over time.
Composite resin fillings are one of the tooth coloured fillings that are commonly used and it is done by sculpting the material directly in the mouth. Porcelain restoration on the other hand is fabricated in the laboratory based on an impression of your teeth and is stronger than the composite fillings.
Thus, many patients are replacing their amalgam for composite or porcelain fillings. Amalgam removal is being done under high speed suction in order to reduce exposure to mercury vapour in the process. The use of rubber dam greatly reduces the patients exposure to mercury vapour.
Situations when amalgam use should be avoided
People who are advised to avoid getting new amalgam fillings or having existing ones removed or replaced (where possible) include:
- Pregnant women – mercury may cross the placenta and enter the bloodstream of the fetus.
- Women who are breastfeeding – mercury may be passed to the baby through breast milk.
- Children – growing and developing teeth are more sensitive to the effects of any chemical substances in the environment, including mercury.
- People with kidney disease – high levels of mercury exposure can affect the kidneys, so exposure to mercury should be minimised for people with kidney disease.
While there is currently no scientific evidence directly linking amalgam with either ill health or birth defects, these recommendations have been made for precautionary reasons.