Aphthous ulcers are painful sores inside the mouth, gums, or lips. They are also called canker sores. The sores can occur one at a time or as a group. Canker sores are temporary and usually not serious.
Canker sores can be various sizes. They typically occur on the inner cheeks and lips, and on or under the tongue. Canker sores are open, shallow, grayish sores. They may have a raised, yellowish-white border surrounded by a red border.
Some people get canker sores 2 to 3 times per year. Others get sores often. The sores may be painful for 3 to 4 days.
Minor sores may last for a total of 7 to 14 days. Major sores can last for several weeks or even months. They may leave a scar after they heal.
The doctor will ask about your symptoms and health history. A physical exam may be done. The doctor may diagnose the sore based on how it looks.
Tests may be done to rule out other causes. They may be:
Aphthous stomatitis. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/aphthous-stomatitis. Accessed February 25, 2021.
Bozca BC, Alpsoy E. Experimental therapeutic solutions for Behcet's disease. J Exp Pharmacol. 2021;13:127-145.
Canker sores. Family Doctor—American Academy of Family Physicians website. Available at: https://familydoctor.org/condition/canker-sores. Accessed February 25, 2021.
Mortada I, Leone A, et al. Oral manifestations of inflammatory bowel disease. J Biol Regul Homeost Agents. 2017;31(3):817-821.
Last reviewed January 2021 by
EBSCO Medical Review Board
Marcin Chwistek, MD
Last Updated: 2/25/2021
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