Oral lichen planus in the mouth of a 65 year old male patient. This is a chronic inflammatory condition that affects the mucous membranes inside the mouth. Common symptoms include white web-like patches, red, swollen tissues, and open sores, which can cause burning, pain, or discomfort. While the exact cause is not completely understood, genetics and immunity may play a role. There is no cure for lichen planus; treatment focuses on helping severe lesions heal and reducing pain and discomfort. Corticosteroids, mouthwashes, and sprays can help alleviate symptoms.