Overview
Aphthous ulcers are also called canker sores; these are a very common kind of mouth sore that affect many people. In general, canker sores are shallow, tender sores that are whitish or yellowish in the middle and red around the edges. They tend to occur on the inner lips or cheeks, the gums, and the top of the mouth. There are different methods of classifying the ulcers based on their size; most people develop minor ulcers, which are quite small, and some people develop major ulcers, which are big (up to a centimeter in diameter.) No one is sure what causes canker sores, but some people are more prone to them. There are likely many factors that do cause them, such as different viruses, being stressed, lack of sleep, having poor nutrition, or small injuries to the mouth caused by biting, toothpastes, or foods. There is no cure for canker sores, but sometimes a topical steroid cream or numbing cream can make them feel better. Because no one is sure what causes them, it is hard to know how contagious they are, but it is probably best to avoid intimate contact, such as kissing, while the canker sores are open and painful.
