Canker sores (aphthous ulcers) are a type of mouth sore which commonly arises on the unattached mucous membranes inside the lips and cheeks, on the sides of the tongue, and floor of the mouth. They are not commonly found on the attached, keratinized gingival tissues that surround the teeth.
Canker sores are characterized by red borders with a yellow-grey center, and are typically very painful. Those that are smaller than one centimeter in diameter are considered minor variant apthae, while those greater than one centimeter are considered major variant subtypes.
Aphthous Stomatitis is a term for multiple affected sites. It is very painful and can be temporarily debilitating, leading to problems with speech and eating. Canker sores have a tendency to recur in many patients, producing a diagnosis of Recurrent Aphthous Stomatitis (RAS). The term Sutton’s Disease is also used for major variant apthae, which may take longer to heal (up to 30 days) and can produce scarring.
Canker sores may be caused by the body’s immune system. Deficiencies of certain vitamins, including B9 (folic acid) and B12 (cobalamin) have also been suspected. The foaming agent sodium lauryl sulfate (SLS), commonly found in toothpaste has also been implicated.
They are one of the most frequently encountered mouth sores, especially in women. 15% to 20% of the population suffer from them. Generally, they are self-limiting, meaning they resolve on their own without treatment; however, the painful symptoms can be treated with over-the-counter or prescription medications.
Herpetiform aphthous ulcerations are simliar to minor variant apthae, but are generally smaller (2 millimeters or less) and more numerous (up to 100 may be present at any time).