Loose teeth are a dental problem that many people encounter. Many people think that loose teeth are inflammatory and will be fine with some anti-inflammatory drugs, and some even think that they should wait until their teeth are so loose before going to the hospital to have them extracted, because loose teeth are better to extract and they will suffer less. However, not all loose teeth are caused by inflammation, and taking the loose teeth caused by some tumors lightly may delay the treatment. An elderly patient in the outpatient clinic wanted to extract a loose tooth. The examination found that there was a neoplasm around the loose tooth, and the radiograph found that there was resorption of alveolar bone, biopsy, and the diagnosis was gum cancer, but he kept thinking it was inflammation and delayed for 2 months at home before coming to the clinic. A young guy, the earliest symptom was that he felt loose teeth and could not eat well, thought it was gum inflammation, and used anti-inflammatory drugs and mouthwash for a long time, but not only did it not improve after several months, but several surrounding teeth also loosened, and the lower lip also became numb. Radiographs revealed significant damage to the lower jaw bone, biopsy, and a diagnosis of osteosarcoma. A young girl had always thought she was fat, one side of her face slowly became larger and her teeth appeared loose, and 1 year of weight loss had no effect. A radiograph in found a significantly enlarged jaw bone on one side with a multi-roomed cystic shadow, and the diagnosis was enucleated cell tumor. Due to the large mass, part of the jawbone needed to be removed. …… There are many more cases. These patients were not thought of in the early stages and came to the clinic with a delay and the lesion had developed to a relatively large size. The reason why tumor causes loose teeth lies in the fact that because of the growth and invasion of tumor gradually leads to the resorption of alveolar bone, losing the support of alveolar bone, the teeth become loose. Clinically, tumors that cause loose teeth may be benign or tumor-like lesions, such as jaw bone cyst, enamel cell tumor, etc.; or they may be malignant, such as gum cancer, central jaw bone cancer, bone sarcoma, mucous epidermis-like cancer in jaw bone, malignant lymphoma in the alveolar area, etc. For loose teeth caused by malignant tumors, they should not be extracted to avoid the spread of tumors. The loose teeth should be removed together with the tumor. It is important to emphasize that the most common causes of loose teeth are periodontitis, trauma, periapical infection, etc. The incidence of loose teeth due to tumors is not high, especially malignant tumors of the jaw bone, the incidence is low. It is recommended to visit the hospital as soon as possible when: 1. there are new organisms around the loose teeth; 2. the loose teeth are accompanied by jawbone expansion; 3. there are symptoms such as numbness and abnormal sensation; 4. the long-term anti-inflammatory effect is not effective.