Recurrent aphthous stomatitis (canker sores, or aphthous ulcers) is the presence of small, painful sores (ulcers) inside the mouth that typically begin in childhood and recur frequently.
Mouth injury, stress, and some foods may trigger an attack.
People feel burning pain, and a day or so later a canker sore develops on the soft tissue of the mouth.
Doctors or dentists make the diagnosis based on the pain and the appearance of the canker sores.
Treatment is with mouth rinses and sometimes corticosteroids.
(See also Mouth Sores and Inflammation.)
Recurrent aphthous stomatitis (RAS) is very common. The cause is unclear but probably involves multiple factors, including disorders or abnormal function of the immune system, exposure to preservatives and toothpaste ingredients, and a genetic predisposition. RAS usually begins in childhood, and most people with RAS are < 30 years old.
People who have RAS get canker sores repeatedly. Some have only one or two canker sores a few times a year. Others have almost continuous outbreaks. Attacks usually decrease in frequency and severity with aging.
Many factors seem to predispose to or trigger attacks, but allergic reactions do not seem to be involved. Such factors include injury to the mouth, stress (for example, a college student may get canker sores during final exam week), and certain foods (particularly chocolate, coffee, peanuts, eggs, cereals, almonds, strawberries, cheese, and tomatoes). People with AIDS often have large canker sores that persist for weeks.
R P. MARAZZI/SCIENCE PHOTO LIBRARY
Symptoms of RAS
Symptoms usually begin with pain or burning, followed in 1 to 2 days by a canker sore. There is never a blister. Pain is severe—far more so than would be expected from something so small—and lasts 4 to 7 days. The canker sores almost always form on soft, loose tissue such as that on the inside of the lip or cheek, on the tongue, on the floor of the mouth, on the soft palate, or in the throat. Sores appear as shallow, round, or oval spots with a yellow-gray center and a red border. Usually, sores are small, about 1/8 to 3/8 inches (less than 1 centimeter) in diameter, and often appear in clusters of 2 or 3. They usually disappear by themselves within 10 days and do not leave scars. Larger sores, about ½ to 1½ inches (less than 3 centimeters) in diameter, are less common. These larger ulcers are irregularly shaped, can take many weeks to heal, and frequently leave scars.
People with a severe outbreak may also have a fever, swollen lymph nodes in the neck, and a generally run-down feeling.
Diagnosis of RAS
A doctor or dentist identifies recurrent aphthous stomatitis by its appearance and the pain it causes.
Treatment of RAS
Pain relievers
Mouth rinses
Corticosteroids taken by mouth
Treatment consists of relieving the pain with the same general measures used for other mouth sores (see Topical treatmentsCandida albicans (see Symptoms of Candidiasis).
oral herpes simplex infection, which would be made worse by taking corticosteroids. Corticosteroid rinses and tablets are absorbed by the body more than are corticosteroids given in gel form, so the side effects may be a concern (see sidebar Corticosteroids: Uses and Side Effects).
More Information
The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
MouthHealthy.org: Provides information on oral health, including nutrition and guidance on selecting products that carry the American Dental Association's seal of approval. There is also advice on finding a dentist and how and when to see one.
