The floating feeling of teeth after dry pulp surgery is considered to be related to apical periodontitis and periodontitis. 1. Periapical periodontitis: After endodontic surgery, if the treatment of pulpitis is not thorough enough, it can cause the bacteria left in the pulp cavity to multiply, or the medication leakage leads to the inflammatory reaction of the root tip, and the early stage of periapical periodontitis can show the tooth floating sensation and occlusal pain, etc. Usually, it is necessary to carry out root canal treatment. 2. Periodontitis: If the endodontic operation is not careful or do not pay attention to dental hygiene after the operation, can cause periodontitis, acute periodontitis will cause edema of the periodontal ligament phenomenon, will also cause tooth loosening, resulting in tooth floating sensation, such a situation needs to be periodontal rinsing, anti-infective treatment. This situation requires periodontal rinsing and anti-infective treatment. The feeling of teeth floating out after endodontic surgery may also be related to other reasons, so it is recommended to consult a doctor in time to clarify the cause of the disease and carry out standardized treatment.