Melasma mandibular

Fig. 14.5a, b. Mandibular melasma before and after superficial peeling with 25% salicylic acid... 

Melasma on the forehead centrofadal. Other kinds of melasma include malar and mandibular. 

Melasma is a chronic recurrent acquired symmetric cutaneous hypermelanosis, representing a dysfunction of the pigmentary system. Characterized by irregular brown, grayish brown, or tan macules and patches occurring on sun-exposed skin areas, it mostly involves the forehead, malar eminences, mandibular areas, and cutaneous part of the upper lip. Melasma develops slowly, can last for many years, worsens in summer and improves in colder seasons. It may be called chloasma and mask of pregnancy but the widely accepted term for this entity is melasma. 

Bilateral symmetric uniformly hyperpigmented lesions are seen in three clinical patterns [68,98,123,126] Centrofacial (63-64%) - cheeks, forehead, upper lip, nose, and chin Malar (21-27%) - cheeks and nose Mandibular (9-16%) - ramus of the mandible Other areas which may be involved are the dorsal forearms [68], rarely on the nipples and external genitalia [8]. Melasma does not involve the mucous membranes [123]. 

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