For about two years, fixed aligners are required, with an average of four to six weeks of follow-up visits to the hospital to have the aligners adjusted by the doctor. The main reason for the length of orthodontic treatment is that the doctor makes the patient’s teeth move in the skeleton to align the teeth and improve the bite. This process simulates the process of tooth eruption and skeletal remodeling to achieve non-invasive. Tooth movement is actually the process of skeletal remodeling, a non-invasive remodeling of the skeleton, and the desire for speed is not achieved. To move the teeth to conform to the physiological law, generally every month to review, each time the doctor will adjust, add a little force, generally need to review about 20 times to achieve the effect, a count is almost almost two years, there are also some simple malocclusion treatment can be in six months, a year to end. More serious malocclusion, or the patient’s lack of cooperation, will also lead to a longer course of treatment.