Everyone at some point in life experiences discomfort and pain in the mouth due to sores, which depending upon their shape can be due to a fever. It may be a cold sore, mouth ulcer, or canker sore.
Ulcers are caused by trauma to the mouth (brushing, biting with the teeth, or by a foreign object). They usually heal on their own in a short period of time and are shallow.
1. An allergic reaction hypersensitivity to certain foods.
2. A minor injury to the mouth from dental work, excessive tooth brushing, sports accidents, or accidental cheek biting.
3. Stress
4. Injury from brace