LARGE IRREGULAR PIGMENTED MACULE IN THE POSTERIOR EDENTULOUS MANDIBULAR ALVEOLAR RIDGE

Abstract

We report an unusual case of a 1.5-cm dark macule on the edentulous posterior mandibular alveolar ridge. The lesion affected a 62-year-old woman referred by a clinician to the oral medicine service with suspect of melanoma. Clinical investigation found no signs of pain and discomfort. The patient stated she had not noticed the lesion previously. An excisional biopsy was performed and during the excision a loose brownish granular material within the submucosa and over the mandibular bone surface was seen. This material was curetted and submitted for microscopic evaluation. The histopathologic report described a loosely organized connective tissue with blackened granular agglomerates that also stained the elastic collagen fibers dispersed in the matrix and in the vessel wall leading to a foreign body–type granuloma with focal argyrosis (amalgam tattoo). Postsurgical follow-up of 11 months was uneventful. We report an unusual case of a 1.5-cm dark macule on the edentulous posterior mandibular alveolar ridge. The lesion affected a 62-year-old woman referred by a clinician to the oral medicine service with suspect of melanoma. Clinical investigation found no signs of pain and discomfort. The patient stated she had not noticed the lesion previously. An excisional biopsy was performed and during the excision a loose brownish granular material within the submucosa and over the mandibular bone surface was seen. This material was curetted and submitted for microscopic evaluation. The histopathologic report described a loosely organized connective tissue with blackened granular agglomerates that also stained the elastic collagen fibers dispersed in the matrix and in the vessel wall leading to a foreign body–type granuloma with focal argyrosis (amalgam tattoo). Postsurgical follow-up of 11 months was uneventful.