What causes aphthous stomatitis?

Although there are some well-established triggers, the cause of aphthous stomatitis is often unknown.

For example, the most common form of aphthous stomatitis causes painful “canker sores,” occurring one or two at a time, and lasting 7-10 days; a specific cause is rarely identified.

When a cause or trigger can be identified, aphthous ulcers may be attributed to:

•    injury to the lining of the mouth, tongue or palate
•    stress
•    an allergic reaction
•    a reaction to a medication or a toxin or chemical in certain foods, drinks or toothpaste
•    vitamin or nutrient deficiency (such as iron, folate or B12 deficiency)
•    immune-mediated disease, including celiac disease, Behcet disease, Crohn disease or lupus
•    poor dental hygiene
•    newly acquired HIV Infection
•    low white blood cell count