The tooth is like a tree that grows firmly in the soil, with the trunk standing on the ground and the roots buried deep in the soil. Only the roots and the alveolar bone are held together by millions of elastic fibers. These fibers, which suspend the tooth roots in the middle of the alveolar bone, are medically known as the periodontium. Under normal circumstances, teeth can have a certain amount of slight looseness, which is mostly produced when chewing food, and when the doctor shakes the tooth with an instrument, he can find a degree of tooth shaking within a millimeter. This is a physiological movement, which has a certain protective effect on the teeth. 1.The teeth can be shaken by bruises, falls or excessive bites. This is because the periodontal membrane is injured by excessive external force, and the elastic fibers between the tooth and periodontal membrane are damaged, which makes the tooth loose. 2.Tooth loosening caused by periodontal disease. The periodontal membrane is subjected to chronic inflammatory stimulation for a long time, so that the periodontal membrane fibers are gradually degenerated and destroyed. When these periodontal tissues supporting the teeth are gradually destroyed, the teeth will become loose. 3, periodontal degeneration can cause most teeth to loosen. Periodontal degeneration occurs mostly in young people due to degenerative changes in periodontal tissues, destruction of periodontal fibers and resorption of alveolar bone, resulting in loosening and displacement of teeth. The loosening of teeth caused by periodontal degeneration occurs first in the upper and lower front teeth and the first molar, as the teeth are shifted, the previously aligned teeth become thinner, the upper front teeth protrude outward, and gaps are created between the teeth. Although periodontal degeneration is rare clinically, it is very harmful and can often cause young people to lose all their teeth at an early stage, so attention should be drawn to it. 4, acute periapical inflammation, jaw bone osteomyelitis, tumors in the jaw bone can cause loosening of the teeth of diseased teeth. Some diseases that can affect the gums and periodontal support tissues, such as necrotizing gingivitis, vitamin deficiency, diabetes, etc., can also cause loosening of teeth. The treatment of loose teeth should be prompt for the cause and most patients can be cured. When periodontal disease develops to a more serious degree, most teeth will become loose, characterized by extensive destruction of periodontal supporting tissues, which seriously affects chewing function. Together with symptoms such as overflowing pus, bleeding, and bad breath, this has an extremely negative impact on the patient’s physical and mental health. Although most of the causes of tooth movement are complex and used to be considered incurable, in recent years, with the development of medical technology, the treatment effect has been improving, and many patients have not only retained the affected teeth but also maintained their chewing function after active treatment. Therefore, it is extremely necessary for patients to go to the hospital as soon as possible to get timely treatment, otherwise there is a high risk of premature loss of the affected teeth or even the loss of the entire mouth. Tooth loosening is a chronic disease with a long course of treatment, and because of the complex etiology, the methods of treatment are also multifaceted. In the treatment of the whole body, attention should be paid to improving the resistance of the body, increasing nutrition and strengthening the body, in the local treatment, mainly controlling the inflammatory infection, learning the correct method of brushing teeth and maintaining oral hygiene. Patients with tartar should go to the hospital regularly to remove the tartar and so on, suffering from periodontal pockets, periodontal often swollen, overflowing pus must be surgically treated to remove the periodontal pockets of granulation tissue and subgingival calculus, so that the periodontal support tissue regeneration, recovery, loose teeth can be used wire ligation or splint fixed, so that loose teeth support each other, rely on, to achieve relative stability, can withstand a certain force effect.