Canker Sore


This is a painful ulcer you get in your mouth. It can form inside your lip, on or under your tongue, on your gum, on your cheek or on the roof of your mouth.


We don't always know why canker sores form. They may be linked to things like stress, hormones, diet, injury, or sensitivity to food or toothpaste. They may also be linked to certain conditions and diseases. These sores don't spread from person to person.


Canker sores are often white with a red border. They can be small or large, and may be circular or oval-shaped. Some have irregular borders. An uncommon form, called "herpetiform" canker sores, are the size of pinpoints. They may group in large clusters in your mouth to form one large sore.


Most canker sores don't need treatment. They heal on their own after one to six weeks. A sore that's large or deep may leave a scar. You can help avoid canker sores by managing stress, practicing good oral hygiene, and by making sure braces or other appliances don't poke your mouth. Eat a healthy diet, and avoid foods or drinks that irritate your mouth. Talk to your dentist or doctor for more information.