But if the blue-gray spot grows or changes color, there is a good possibility it may not be an amalgam tattoo.

Amalgam tattoos pose no harm.

Called amalgam tattoos, they occur when a tiny piece of amalgam filling gets embedded in your cheek or gum.

Amalgam tattoos pose no harm, but it's not likely an amalgam tattoo if the blue-gray spot grows or changes color.

Similar hyperpigmentations can be due to physiological pigmentation, amalgam tattoo, suntan, drug-related melasma, Addison's Disease, or post-inflammatory hyperpigmentation.

Other endogenous pigments can be overproduced to influence the color, e.g. bilirubin in bilirubinemia or hemosiderin in hemochromatosis, or exogenous pigments such as heavy metals can be introduced into the mucosa, e.g. in an amalgam tattoo.