Pain after biting into hard objects is a more serious phenomenon, suggesting that there are cracks on the surface of the tooth and dentin, and timely medical attention is needed. 1. A fissure is a small crack that extends from the crown of the tooth to the root of the tooth, usually causing tooth breakage or biting pain, and is associated with daily bite dysfunction or long-term chewing of hard objects. Since cracked teeth can cause painful chewing and the damage is not self-healing, they need to be treated as soon as possible. 2. Patients with a mild fissure can choose conservative treatment or regular observation. If the crack is more obvious or causes significant biting pain, early filling and restoration of the crack is recommended. If the crack is too severe or has caused tooth fracture, root canal treatment followed by crown restoration should be considered. It is recommended that people with cracked teeth or other periodontal diseases should be treated as soon as possible and have regular oral checkups. Do not chew hard objects too much in your diet.