An amalgam tattoo is an area of discoloration in the mouth caused by the migration of particles of dental amalgam which become embedded under the oral membranes, causing a patch of gray, black, or blue to appear. Amalgam tattoos are very common in people who have fillings and crowns, and they are not a cause for concern, unless people are bothered by their appearance. However, some oral cancers can look like amalgam tattoos in their early stages, so it is important to confirm that a dark patch is indeed an amalgam tattoo, and not something more sinister.
Most commonly, amalgam tattoos form during dental procedures, in which flecks of amalgam may be accidentally chipped off and embedded in the gums, cheeks, roof of the mouth, or tongue. Dentists can reduce the risk of this by using protective dams in the mouth for procedures. It is also possible for a filling or crown to rub off on the surrounding tissue, causing a dark blotch to appear on the membranes of the mouth. Usually, the patch of color is small and isolated.
Many people with these marks are unaware that they have them. An amalgam tattoo may be identified by a dentist during a routine checkup, or spotted by a sharp-eyed friend or doctor. When a dark patch does appear in someone's mouth, a dentist will usually review the patient's dental history and take x-rays to confirm that the spot is an amalgam tattoo. Flecks of metal in the x-ray and a history of filled teeth or crowns usually verify the diagnosis, although it is also possible to take a biopsy for study.
If an amalgam tattoo grows, changes shape, or becomes very tender to the touch, it may be a sign of oral cancer or another dental problem. People should keep an eye on their amalgam tattoos, and they should discuss any changes which occur with a dentist. Catching the signs of a more serious problem early increase the probability of resolving the problem painlessly and quickly. Treatment for dental problems should never be delayed, as the problem will only get more complex and more challenging to treat with time.
Some people are bothered by irregular mouth pigmentation, especially if it appears around the lips. A minor surgery can be used to remove the discolored area of the mouth. A dentist may also recommend replacing an older filling or crown to reduce the amount of free-floating dental amalgam in the mouth so that the discoloration does not recur.