Canker sores are painful sores that usually appear inside your mouth, at the base of your gums. While these are not ...

What is the difference between a canker sore and a cold sore? Canker sores and cold sores are common but distinct oral ...

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Cold sores occur on the outside of the mouth and are caused by the herpes simplex virus. Canker sores are blisters inside the mouth that can occur due to injury, nutritional deficiencies ...