Tooth decay, i.e. tooth decay, can fall off naturally if it is already rotten and empty, but it will be accompanied by many complications, so it is advisable to extract it as soon as possible. Inflammation is a very important factor influencing the occurrence of tooth decay. If the tooth decay has rotten and empty, it will probably lead to periapical inflammation and even periodontal disease before it falls off naturally, which will eventually make the alveolar bone resorption. The resorption of the alveolar bone is the biggest obstacle to the restoration of teeth later, especially when dental implants are needed. Therefore, when tooth decay occurs, the patient should start treatment as early as possible to determine whether the tooth can be retained or not. If it is determined that the pulpal floor has been eroded, it does not need to be retained and should be extracted as soon as possible. After extraction, depending on the state of the alveolar bone, different restorative methods are chosen and some preparations for restoration are made in advance, which will help more in restoring the chewing function. Patients can have relevant examination in dentistry, such as taking dental film, to determine the apical condition of caries and judge its treatment value.