Description: An amalgam tattoo is a localized area of blue-gray or black pigmentation. The amalgam is relatively inert and usually causes no tissue damage. The discoloration is permanent.
Etiology: The accidental and usually unavoidable implantation of dental amalgam in oral soft tissues produces this lesion.
Treatment: None required.
Prognosis: Good
Differential diagnosis: Differential diagnosis is ordinarily not a problem. Amalgam tattoo should easily be distinguished from nevi, which are usually brown. The rare blue nevus may resemble amalgam tattoo .