Oral submucous fibrosis (or OSF) is a chronic,complex,irreversible,highly potent pre-cancerous condition characterized by juxta-epithelial inflammatory reaction and progressive fibrosis of the submucosal tissues (lamina propria and deeper connective tissues). As the disease progresses, the jaws become rigid to the point that the sufferer is unable to open his mouth. The condition is linked to oral cancers and is associated with areca nut chewing, the main component of betel quid. Areca nut or betel quid chewing, a habit similar to tobacco chewing, is practiced predominately in Southeast Asia and India, dating back thousands of years.