Orthodontic treatment will not cause any serious harm or sequelae as long as you have regular checkups and keep your teeth clean. If the treatment is not standardized, the possible sequelae mainly include loose teeth, alveolar bone damage, root resorption. And its harm has easy to complicate gingivitis, root fracture and other diseases. 1.Sequelae of orthodontic teeth: (1) loose teeth: in the process of orthodontic surgery, due to violent operation or later complication of infection, it will lead to displacement of teeth and loosening. (2) Alveolar bone damage: in the process of moving the teeth, improper operation and other factors will lead to external forces directly on the root of the teeth, damage to the alveolar bone. 2. Hazards of orthodontic treatment: (1) gingivitis: there will be tissue damage in the process of orthodontics, resulting in bleeding blood vessels, bacteria inside the mouth will be more easily infected, causing inflammation of the gums. (2) Root resorption: orthodontic surgery may cause changes in the stress point of the teeth, inappropriate biting action, root resorption will occur, resulting in shorter roots.