Clinically, we often hear patients ask: Are orthodontically treated teeth prone to loosening and falling out? In the process of orthodontic treatment, patients will feel the whole mouth teeth chewing weakness and loosening, so it is not surprising to have such inquiries and concerns. Here, we can definitely tell our patients that such worries are not necessary, as teeth will not loosen and fall off after orthodontic treatment. Orthodontic treatment is the application of external force or removal of abnormal muscle force on misaligned teeth or malformed jaws, which causes alteration of the alveolar bone and periodontal tissues to move the teeth to the desired position through the internal reaction of the body, so that the dental and maxillary system can be improved in form and function. However, tooth movement is not a purely mechanical movement, it is under the control of strict orthodontic force, through the person’s own growth potential and the plasticity of the jawbone to make the alveolar bone on the one hand resorption and on the other hand proliferation, so as to complete the reconstruction of the alveolar bone and the movement of the teeth. Therefore, when the orthodontic force is removed, the teeth can be reconstructed in the new position with normal periodontal structure and restore its function. Therefore, patients and friends absolutely do not need to worry that their teeth will be loosened and fall off when they get older because they have had orthodontic treatment.