Description

Pigmentation of oral mucosa is caused by pigments leading to change in colour of tissues. It can be endogenous or exogenous. Melanin, haemoglobin, hemosiderin, and beta-carotene are responsible for endogenous pigmentations. The majority of brownish pigmentation is physiological, however occasionally it might be a sign of serious disorders. Clinical manifestations of physiological pigmentation of the oral mucosa include multifocal or diffuse melanin pigmentation, which varies in prevalence across different racial and ethnic groups. The patient may not become aware of the patient’s physiological colouring until much later in life. Brown in colour, ranging from light to dark. Early in intrauterine development, melanoblasts, which are progenitors of melanocytes, go from the neural crest to the epidermis and hair follicles before differentiating into dendritic cells. After roughly 10 weeks of gestation, melanocytes first emerge in the head and neck region of the body.

Intra-oral examination of this patient shows diffuse, well demarcated, smooth, brownish pigmented lesion, present on dorsum surface of the tongue which is non tender and non-scrapable.

Figure 1: