Ulcers in the mouth have many causes.
Traumatic ulcers may occur in sites of trauma due to biting the oral mucosa or due to a sharp cusp or restoration or component of a denture. Occasionally chemical trauma may occur due to topical application of aspirin or thermal trauma due to a burn from hot food or drink. These usually heal when the trauma is relieved.
Recurrent mouth ulcers called recurrent aphthous stomatitis, is a common condition which may cause considerable discomfort. No single causative factor is usually identified. Blood tests are usually advised to exclude anaemia or a deficiency in iron, folic acid or vitamin B12. Treatment is available to help reduce the suffering from this condition which may include simple mouthwashes, topical steroids or sometimes drugs.
Oral cancer may present as an ulcer which persists in the mouth for more than 2 weeks. The higher risk sites are the sides of the tongue and the floor of the mouth, under the tongue. Oral cancer most commonly occurs in patients who smoke, drink alcohol or chew pan, although are increasingly seen in young adults without these risk factors. Any ulcer in the mouth which persists for more than 2 weeks should be checked by an oral healthcare professional. A biopsy may be required.
Persistent oral ulceration may also occur in association with dermatological conditions (lichen planus, pemphigoid, pemphigus), gastrointestinal conditions (Crohn's disease, ulcerative colitis, coeliac disease), Haematological conditions (HIV, Graft v Host Disease, mucositis) and as a side effect of drugs (nicorandil).