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|
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.