A Rare Case of Oral Mucosal Pigmentation: Differential Diagnosis and Case Presentation JCDA SciELO Brasil Variations of oral anatomy and common oral lesions Variations of oral anatomy and common oral lesions SciELO Brasil Lingual melanotic macule the first case report in an adult patient Lingual melanotic macule the first case report in an adult patient Dark spot on lip appeared randomly : r Blackskincare Oral Melanotic Macule MEDizzy