[Treatment and analysis of a clinical case of gingival pigmentation around the restored teeth].

A remarkable gingival pigmentation around the restorated teeth was successfully treated by simple surgical removal; incision & coagulasion of deposits by electrosurgery. Before the treatment, a biopsy from the pigmented gingiva was histopathologically examined, and a lot of small pigment deposits were found in the lamina propria with no inflammation, but not in the epitherium. Elements constructing the deposits were also determined by means of an electron probe X-ray microanalyser. Silver was found to be the principal element of the deposits, but not found at all in the crown metal. These results suggested that the cause of the pigmentation was implantation of metal fragments from metal cores during abutment teeth preparation. Therefore, the surgical removal was performed. Relapses have not occurred for 3 years since the treatment.