In clinical practice, we often see many patients who say that when they eat, they can’t use their big teeth at the back and they can’t chew food because their teeth are moving. For this problem, the clinical situation is mainly based on the looseness of the teeth. There are three degrees of tooth loosening: I degree loosening, II degree loosening and III degree loosening. Loose teeth of degree III need to be extracted and have no retention value. If the patient is in the second degree of looseness and the first degree of looseness, we should conduct routine examination for the patient’s loose teeth, through auxiliary examination, take X-ray film to see the condition of teeth and alveolar bone, whether the periodontal membrane is destroyed and absorbed, including the presence of subgingival calculus, and the need to do scaling and scraping, according to these conditions to determine whether the teeth should be retained or extracted. If the tooth has retention value, the tooth will be retained through routine scaling and scraping as well as endodontic treatment including apical treatment. However, not all teeth can be preserved by these methods. Because the periodontal condition of each patient is different, including the patient’s post-treatment and post-operative prognosis are also different. Therefore, for loose teeth, especially large teeth, and loose teeth in the back, the decision of whether to keep or extract is based on each patient’s situation and condition.