What Caused These Multiple Hyperpigmented Macules of the Mouth? This lovely patient was thrilled with her beautiful result after laser treatment of oral melanotic macules. I share this case to educate: laser treatment requires accurate diagnosis, an understanding of the differential Differential Diagnosis of Pigmented Lesions in the Oral Mucosa: A Clinical Based Overview and Narrative Review 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