The diagnosis of oral mucosal pigmentations is complex, and
histopathological evaluation may be necessary to clarify the nature of the lesion.
Although most oral pigmented lesions are benign, it must be emphasized that
melanoma of the oral cavity, probably the most aggressive epithelial tumor, is often
underestimated and diagnosed late. The dentist, therefore, should have basic knowledge
of the main epidemiological and clinical characteristics of this large group of lesions.
Pigmented lesions associated with melanin include racial pigmentations, melanotic
macules, smoking-associated melanosis, melanocytic nevi, melanoacanthoma, and
melanoma. Some systemic diseases (for example, Peutz-Jeghers syndrome and
Laugier-Hunziker syndrome) are also characterized by the presence of melanin lesions
in the oral mucosa. In the literature, there are also some cases of pigmentation caused
by melanin in association with the intake of drugs and as a consequence of some postinflammatory mechanisms. Pigmented lesions not associated with melanin are
subdivided according to the nature of the pigment responsible for the discoloration. The
pigmentations caused by the deposition of exogenous pigments are represented by
some metals (for example, amalgam, tattoo), drugs, or their metabolites.
Keywords: Melanotic macules, Nevus, Pigmented lesions, Racial pigmentations, Smoker’s melanosis.
