Fracture plane of unknown depth and direction passing through tooth structure that, if not already involving, may progress to communicate with the pulp and or periodontal ligament
Complete or incomplete fracture extending to the cervical third or the root surface. The pulp is normally vital, with mild symptoms on biting and to cold
Crack initiated at the root level, usually in a bucco-lingual direction. The crack may be complete or incomplete and almost all cases have a history of root canal treatment