Our Canker Sores Main Article provides a comprehensive look at the who, what, when and how of Canker Sores

Definition of Sore, canker

Sore, canker: A small ulcer crater in the lining of the mouth that is often painful and very sensitive. Also known as an aphthous ulcer.

Canker sores are one of the most common problems that occur in the mouth. About 20% of the population (1 in 5 people) have canker sores at any given time. Canker sores typically last for 10-14 days and they heal without leaving a scar.

Picture of a canker sore
Picture of a canker sore

The word "canker" comes from the Latin "cancer" for crab. (In Latin "cancer" was once pronounced kanker from which came canker). Chronic ulcers might seem as hard as a crab shell.


Last Editorial Review: 9/28/2012

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