Canker sores, also called aphthous ulcers, are small, shallow lesions that develop on the soft tissues in your mouth or at the base of your gums. Unlike cold sores, canker sores don't occur on the surface of your lips and they aren't contagious. They can be painful, however, and can make eating and talking difficult.
Most canker sores go away on their own in a week or two. Check with your doctor or dentist if you have unusually large or painful canker sores or canker sores that don't seem to heal.
Most canker sores are round or oval with a white or yellow center and a red border. They form inside your mouth — on or under your tongue, inside your cheeks or lips, at the base of your gums, or on your soft palate. You might notice a tingling or burning sensation a day or two before the sores actually appear.
There are several types of canker sores, including minor, major and herpetiform sores.
Minor canker sores are the most common and:
Major canker sores are less common and:
Herpetiform canker sores are uncommon and usually develop later in life, but they're not caused by herpes virus infection. These canker sores:
Consult your doctor if you experience:
See your dentist if you have sharp tooth surfaces or dental appliances that seem to trigger the sores.
The precise cause of canker sores remains unclear, though researchers suspect that a combination of factors contributes to outbreaks, even in the same person.
Possible triggers for canker sores include:
Canker sores may also occur because of certain conditions and diseases, such as:
Unlike cold sores, canker sores are not associated with herpes virus infections.
Tests aren't needed to diagnose canker sores. Your doctor or dentist can identify them with a visual exam. In some cases, you may have tests to check for other health problems, especially if your canker sores are severe and ongoing.
Canker sores often recur, but you may be able to reduce their frequency by following these tips:
To help relieve pain and speed healing, consider these tips:
Anyone can develop canker sores. But they occur more often in teens and young adults, and they're more common in females.
Often people with recurrent canker sores have a family history of the disorder. This may be due to heredity or to a shared factor in the environment, such as certain foods or allergens.