Summit Enlighten Laser to treat labial melanotic macules on the lip before and after. Facebook Does anyone know what this black mark on my lip is? Started last August so it's I've had it nearly a year, was living in Spain at the time for 6 months An oral melanotic macule is a harmless dark spot found on the lip, most often the lower lip, or inside the mouth, either on the gums, inside the cheek, or on the roof of the mouth. An oral melanotic Oral Malignant Melanoma Oral Cancer Foundation Information and Resources about Oral Head and Neck Cancer