While it is possible to have an allergic reaction to an amalgam filling, the incidence is rare.
What are amalgam fillings?
As the name suggests, dental amalgam is a mixture of several compounds – namely mercury combined with silver, tin, zinc and copper.
Why might I be allergic to an amalgam filling?
A patient who is allergic to mercury or any of the other metal compounds in the amalgam may experience an adverse reaction if exposed over a long period of time.
What are the symptoms of an allergic reaction?
The reaction may present with or without pain but almost always manifests as redness or itching inside the mouth, similar to an allergic skin reaction. This redness is known as a contact lichenoid reaction (because the resulting lesion is shaped like the plant lichen). The cheeks and sides of the tongue are the most commonly affected sites.
Similar symptoms might also be experienced when amalgam fillings are NOT the cause. For example, a broken filling with a sharp or rough surface is liable to cause a similar contact irritation. Non-contact lichenoid reactions are also possible – for example, after exposure to spicy foods, some toothpaste additives and preservatives, and some medications.
What should I do if I think I’m allergic?
If you suspect you are having an allergic reaction to an amalgam filling, your dentist can replace the filling using a tooth-coloured material called composite resin or one of other available filling materials.