Saroj, a 32 - years-old female, from rural background presented with a history of chronic tobacco chewing since 14 years of age. Now she has difficulty in opening her mouth. On oral examination, no ulcers are seen. Most probable diagnosis is:

Most probable diagnosis in the Asian female with history of chronic tobacco chewing and difficulty in opening her mouth with no ulcers on oral examination is oral submucous fibrosis. ORAL SUBMUCOUS FIBROSIS Progressive disease in which fibrous bands form beneath the oral mucosaQ. Almost confined to the Asian populationQ Risk factor for oral cavity malignancies (squamous cell carcinomaQ) RISK FACTORS Pan masala areca nut, with or without concurrent alcohol useQ. Tobacco smoking alone is not associated with oral submucous fibrosis. PATHOLOGY Characterised by epithelial fibrosis with associated atrophy & hyperplasia of overlying epitheliumQ. Epithelium shows changes of epithelial dysplasiaQ. CLINICAL FEATURES Scarring produces contracture, resulting in limited mouth opening & restricted tongue movementQ. TREATMENT Restricted mouth opening can be treated with either Intralesional steroids or surgical excision & skin graftsQ.