Oral submucous fibrosis (OSMF) is a potentially malignant condition mainly characterized by inflammation and fibrosis of the submucosal tissues leading to marked rigidity and reduced opening of the jaws. OSMF has a multifactorial etiology but areca nut consumption is considered to be the most consistent factor in its pathogenesis. There is no definitive treatment available for treating OSMF. Conventional management involves physiotherapy exercises and treating the disease with certain medications such as steroids and homeopathic medications.

OSMF is a chronic insidious disorder of the oral cavity which has a great potential to turn malignant. The clinical manifestations of OSMF comprise of white, marble-like appearance of the oral mucosa with loss of flexibility and formation of palpable fibrous bands extending from the anterior to the posterior region of the oral cavity.Other features include burning sensation on taking spicy food, loss of papillae of the tongue, loss of natural pigmentation of the lips and restricted mouth opening.

There is no definitive treatment available for OSMF due to its complex etiology. The most essential component in the management of OSMF is the discontinuation of the habit of areca nut chewing by the patient followed by conservative or surgical treatment. Currently, steroids are the most commonly used drug group in managing OSMF because of their ability to reduce the inflammatory process and increasing the apoptosis of inflammatory cells thereby decreasing fibrosis. However, they are not very useful in reversing the pathology and restoring mucosal elasticity and can cause mucosal thinning with long term use ultimately resulting in worsening of the symptoms of the disease.

Many in- vitro and in- vivo studies have been conducted to establish the anti neoplastic, anti inflammatory, immunomodulatory, antihypertensive, antimicrobial, anti-parasitic, antioxidant and hypoglycemic properties of N.sativa oil. Among all the constituents of Nigella sativa, Thymoquinone (Tq) is the most pharmacologically active constituent responsible for most of its properties. Nigella sativa has been used widely in different food preparations in the form of a flavoring agent or a spice. It is also recognized as 'safe' in the inventory of United States Food and Drug administration.

Inclusion Criteria:

• Patients with the age of 18 years and above
• Patients clinically diagnosed with Oral submucous fibrosis
• Patients who have not received any treatment for Oral submucous fibrosis in the last three months.
• Patients who are willing to quit the habit of eating pan, gutka and areca nut
• Patients who are willing to attend the follow up visits

Exclusion Criteria:

• Patients who are less than 18 years of age
• Patients who are already using pain medications, corticosteroids or immunosuppressive drugs in any other form
• Patients with a history of malignancy
• Patients presenting with oral lesions other than Oral submucous fibrosis (OSMF)
• Patients who are allergic to the drug material used in the clinical trial
• Patients who will not give consent