A Mouth Ulcer refers to the break or discontinuity in the soft tissue lining of your oral cavity. Your oral cavity's inside and outside (lip region) is lined with a thin, smooth tissue known as mucous membrane. Any trauma, injury, or infection can disrupt this membrane, resulting in small or large ulcers. These ulcers can range from painless to extremely painful, depending on their size, severity, and underlying causative agent. In the majority of the cases, mouth ulcers heal within a specific duration of time with symptomatic treatment only.
There are a variety of different causes for mouth ulcers. They can occur due to traumatic injury, viral, bacterial, or fungal infections, genetic diseases, immunocompromising diseases, allergies, nutritional deficiency, hormonal imbalance, oral cancer, and other factors.
A common cause of mouth ulcers is a traumatic injury that breaks the continuity of the mucous membrane. It can be due to external damage, ill-fitting dentures or prosthetic appliances, broken wires or brackets, the rough edge of a broken tooth, or inadequate fillings. Certain substances such as aspirin, sodium laurel sulfate, etc., can cause chemical injuries to the mucosa.
Among viral infections, the most common cause of mouth ulcers is the Herpes Simplex Virus 1 (HSV-, leading to small fluid-filled blisters on or around the lip region. These are known as cold sores. Other viruses that can cause mouth ulcers include Herpes Zoster, Varicella-Zoster, Coxsackie A virus, and Human Immunodeficiency Virus (HIV). Bacterial infections such as syphilis and tuberculosis can also cause ulcers within your oral cavity. Fungal overgrowth can also lead to oral ulceration in certain patients with a weakened immune system.
Aphthous ulcers or canker sores are other common types of mouth ulcers that are believed to be related to a triggered immune response. Allergies to certain food substances or external factors are another factor. Patients undergoing chemotherapy, radiotherapy, immunosuppressant treatment, or any other disease that suppresses their immune system are also prone to mouth ulcers.
General factors that can result in the formation of mouth ulcers include excessive dehydration, nutritional deficiency, stress or anxiety, hormonal irregularities, menstruation, and smoking. A rare but important cause is oral cancer which can form ulcers that persist long.
Risk factors of mouth ulcers include ill-fitting dentures or prosthetic appliances, braces, sharp edges of a tooth, accidental biting, and poorly done dental restorations. All of these can cause traumatic ulcers in the oral cavity if not managed on time. People with a weakened immune system due to chemotherapy, radiotherapy, immune-suppressing medications, and immunocompromising diseases such as HIV are at a high risk of developing mouth ulcers. Similarly, food or chemical allergies can irritate the mucous membrane too. Smoking and excessive alcohol intake are external factors that can cause oral cancer, which might initially present as a mouth ulcer. Dehydration, nutritional deficiency (especially vitamin C), stress, and anxiety are other risk factors.
Certain research studies show that mouth ulcers are more common in females than males. They can occur at any age depending on their cause, e.g., traumatic ulcers due to dentures are more common among the elderly population.
The signs and symptoms of a mouth ulcer are related to the underlying cause. In case of traumatic injury, the ulcer may appear reddish and can be painful to touch. Some people might experience a burning or tingling sensation before the formation of ulcers inside the mouth. This feature is common for cold sores and canker sores. Ulcers can vary in shape, size, color, and texture depending on the causative agent. You might experience discomfort while eating or chewing food, especially if they are hot or spicy. Rare cases of oral ulcers might present with fever, headache, malaise, and difficulty in swallowing.
Diagnosis of a mouth ulcer requires a detailed medical history and thorough clinical examination to identify the causative factor. Your doctor might ask for any underlying disease, current medications, known allergies, or recurrence of ulcers. Traumatic ulcers are typically diagnosed by clinical examination. Ulcers caused by viral, bacterial, or fungal infections may require a swab test to confirm the diagnosis. Immune system-related ulcers require diagnosis and management of the underlying problem. Any ulcer that persists over 2-3 weeks might need a biopsy to rule out the suspicion of oral cancer.
Other diseases that might present with similar mouth ulcers include lichen planus, pemphigus vulgaris, leukoplakia, oral candidiasis, Bechet’s syndrome, Crohn’s disease, burning mouth syndrome, and HIV.
Treatment of mouth ulcers is dependent on the underlying cause. Traumatic ulcers can be treated by treating the cause of trauma, such as repairing an ill-fitted denture or restoration. Mouth ulcers caused by viral infections usually do not require any treatment because they heal by themselves within 10 to 14 days. Painful ulcers are managed by applying topical analgesics or anesthetics. Brushing twice a day, using antiseptic mouthwashes or warm saline rinses, and maintaining oral hygiene can promote the healing of mouth ulcers.
For painful ulcers, topical analgesics or anesthetics such as lignocaine can reduce the pain and inflammation. In rare cases, topical corticosteroids containing dexamethasone might be prescribed to reduce the pain and severity of mouth ulcers.
Despite many causes, mouth ulcers typically heal with two to three weeks, depending on their cause and severity. If an ulcer persists for a duration longer than two or three weeks without showing any signs of healing, it is suggested to test it for the presence of oral cancer.
The primary prevention methods to reduce the occurrence of mouth ulcers include maintenance of oral hygiene, use of antiseptic mouthwashes (not suggested for more than two weeks), and keeping yourself hydrated. Any nutritional deficiency should be addressed immediately. Regular visits to your dentist can reduce their chance of occurrence by identifying any possible traumatic causes. Identifying the underlying cause and taking precautions are crucial to reducing the formation of ulcers within your oral cavity.
Our clinical experts continually monitor the health and medical content posted on CURA4U, and we update our blogs and articles when new information becomes available. Last reviewed by Dr.Saad Zia on May 07, 2023.