Mouth ulcers are painful areas in the mouth and gums. They are also known as canker sores. While mostly harmless, mouth ulcers can be extremely uncomfortable and make it difficult for some people to eat, drink, and brush their teeth.4
Standard ulcers appear on the inner cheeks and last for about a week. Most are harmless and clear up with no medical intervention. There are three main types of mouth ulcers:4
1. Herpetiform ulcers are a subtype of aphthous ulcers and get their name because they resemble the sores associated with herpes. Unlike herpes, Herpetiform ulcers are not contagious and recur very quickly, it may appear that the condition never gets better.
2. Minor ulcers, which can range in size from about 2 millimeters (mm) up to 8 mm across. These ulcers typically take up to two weeks to get better and can cause minor pain.
3. Major ulcers, which are bigger than minor ulcers and are often irregular in shape, may be raised, and penetrate deeper into the tissue than minor ulcers. They can take several weeks to go away and are likely to leave scar tissue when they clear.
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