Frequently Asked Questions

Q: What is a canker sore?

A: Canker sores are a common ailment, characterized by a small ulcer, white or gray in color, with a red rim. Although there is no definitive cause for canker sores, scientists theorize that bacterial or viral infections may contribute to their occurrence. Irritation or cuts caused by biting the lip or inside of the mouth, as well as stress and fatigue, may also play a role. Canker sores are not contagious.