A canker sore is a painful, open sore in the mouth. Canker sores are white or yellow and surrounded by a bright red area. They are not cancerous.
A canker sore is not the same as a
Aphthous ulcer; Ulcer - aphthous
Causes, incidence, and risk factors
Canker sores are a common form of
Canker sores may also be linked to problems with the body's immune (defense) system. The sores may occur after a mouth injury due to dental work, aggressive tooth cleaning, or biting the tongue or cheek.
Canker sores can also be triggered by:
- Emotional stress
- Lack of certain vitamins and minerals in the diet (especially iron,
folic acid, or vitamin B-12)
- Menstrual periods
- Hormonal changes
Anyone can develop a canker sore. Women are more likely to get them than men. Canker sores may run in families.
Review Date: 02/17/2011
Reviewed By: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.