A tooth may crack for many reasons, such as the following:
- Chewing on hard objects or foods such as pencils, ice, nuts or hard candy
- An accident, such as a blow to the mouth
- Grinding or clenching of the teeth
- Uneven chewing pressure, especially if a nearby tooth is lost
- Loss of tooth structure through wear
- Loss of tooth structure due to large fillings or other restorations
- Exposure of tooth enamel to extreme hot and cold temperatures