When the child’s permanent teeth are loose, oral examination is required, and the treatment plan is formulated after taking full-mouth surface tomography film, as follows: 1. Adjust and grind the pair of (dentition) teeth: If an accidental injury occurs, resulting in periodontal concussion of permanent teeth, the pair of (dentition) teeth can be adjusted and grinded to reduce occlusal contact, avoid gnawing hard objects with the affected teeth, and return to normal after 3-4 weeks of periodontal membrane swelling subsides. 2. Reset the permanent teeth: If the permanent teeth are semi If the permanent tooth is semi-dislocated or completely dislocated, the permanent tooth can be reset in the alveolar socket under local anesthesia, and the full (dental) pad can be made and fixed, and the (dental) pad can be removed after the root is stabilized for 2-3 months. 3.Remove the infected pulp: If acute periapical inflammation occurs in the permanent tooth, resulting in obvious swelling of the gum, accompanied by pus overflow, the pulp can be opened and drained, the infected pulp can be removed, the root canal canal can be flushed with 3% hydrogen peroxide solution, and the canal canal can be closed with calcium hydroxide paste. paste to seal the canal cavity and induce the root to continue developing.