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What is a Canker Sore?

May 5, 2010

Canker sore is a common term used to describe aphthous ulcers inside the oral cavity. They are usually small, shallow, open sores that are extremely sensitive to acidic or salty food and drink. Canker sores are relatively common, but many people that get them often don’t know what to do about them. Instead, they have learned to just ignore them until they go away. They can occur just about anywhere in the oral cavity: along the tongue, inside the cheeks, or on the inner parts of the upper and lower lips.

Where does a canker sore come from and what can we do about them?

Canker sores start out as small red bumps inside the oral cavity. They may be irritated by food or drink or may erupt on their own to reveal an open, shallow ulcer with an inflamed border. While they are usually very small, they can be extremely uncomfortable and may even occur in clusters. The first thing to keep in mind with canker sores is that they are not contagious like cold sores. Cold sores are caused by the herpes simplex virus and are very easy to transmit from person to person. Canker sores are never found on the outside of the oral cavity and, even though doctors aren’t entirely sure what causes them, they are not contagious.

Canker sores may be caused by increased stress levels, menstrual cycle hormones, use of products containing sodium lauryl sulfate, or certain dietary deficiencies. They will go away on their own, but taking care to avoid those risk factors can reduce their occurrence in susceptible people.

Denver Dentistry – Dr. Guy Grabiak, DMD, FAGD
3190 S Wadsworth Blvd, Suite #300
Littleton, CO 80227
(303) 988-6118 ‎

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Denver Dentistry 303.988.6118
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