Pigmented Lesions of the Oral Cavity Oral and Maxillofacial Surgery Clinics Diagnosis of oral pigmentations and malignant transformations ScienceDirect Oral pathology: Noting a pigmented macule that often presents a diagnostic dilemma Registered Dental Hygienists Labial Lentigo (labial melanotic macule) Cancer Therapy Advisor Labial Lentigo (labial melanotic macule) Cancer Therapy Advisor ORAL MELANOTIC MACULE (OMM) (Also called focal melanosis labial melanotic macule) A benign, localized, flat pigmented lesion of the oral mucosa Caused by a focal increase in melanin production