HEALTH INFORMATION

Not all mouth sores are canker sores. Cold sores or fever blisters are a different kind of sore, which is caused by a virus called herpes simplex (say: hur-peez sim-pleks). Cold sores and fever blisters often form outside the mouth, around the lips, on the cheeks or chin, or inside the nostrils of the nose. Unlike canker sores, those sores are contagious. Chickenpox are another kind of contagious sore, and it's possible to get chickenpox inside the mouth.
What Causes Canker Sores?
No one really knows what causes canker sores. But researchers think stress may make a person more likely to get one. A canker sore also may spring up if a person's diet doesn't contain enough vitamins and minerals.
The inside of your mouth is delicate, so mouth injuries, such as biting the inside of your lip or brushing your teeth too hard, also seem to bring on canker sores. But anybody can get a canker sore and they may run in families, which means that if your mom or dad gets canker sores, you might get them, too.