The diagnosis of melanotic and other pigmented lesions of the lips and oral mucosa (dark spots in the mouth).

Pigmented lesions of the oral mucosa may be due to collections of blood, metallic particles of melanin. Any of these substances will appear of a blue tinge if at any depth in the tissues, while superficial collections may be red, black or brown respectively. Lesions associated with blood will be hematomas, dilated veins, hemangiomas or telangiectases. Metallic particles are found in amalgam tattoos. Melanotic pigmentation may occur as a normal variation, following hormonal disturbance and inflammation, and sometimes iatrogenically. Benign and malignant melanoma of the oral cavity is highly lethal. 25% of malignant melanomas in this site present as nondescript brown spots, and isolated broid overlooking an early malignant melanoma.