Oral submucous fibrosis: An update on current theories of pathogenesis.

Over the last 40 years, many theories linking oral submucous fibrosis (OSMF) to various risk factors have been proposed. Spicy, pungent foods and irritants such as supari (areca nut), paan (betel leaves), tobacco (through chewing or smoking)-the common Asian habits of chewing the aforementioned agents-have all been incriminated as causative agents. Systemic factors such as nutritional deficiency, genetic predisposition and autoimmunity have also been proposed in the pathogenesis of OSMF. However, the precise aetiology of OSMF is still unknown, and no conclusive evidence has been found despite many extensive investigations on implicated factors. Most of the ideas proposed have been derived from the existing clinical and epidemiological data. We present a comprehensive review of the various theories regarding the pathogenesis of the condition, but have not concentrated on malignant transformation in this article.