Most orthodontic treatment takes between 1-2 years, but there is some variability in the length of treatment due to individual age, degree of deformity, and treatment modality. First of all, the age of the patient is an important factor affecting the length of orthodontic treatment. Because the body skeletal system is still in the growth and development stage during childhood, the oral jaws can be reshaped relatively strong at this time, so the length of orthodontic treatment for such patients will generally be relatively short, taking about 12 months. While adult patients, their skeletal system has entered a solid period, so the length of orthodontic treatment needs to be properly extended, the specific length of treatment from 18-24 months. In addition, if the patient has more serious cases of sparse teeth and misaligned teeth, the treatment period needs to be longer in order to achieve the ideal treatment effect. At present, orthodontic treatment can be divided into functional brackets, movable brackets, fixed brackets three major ways, according to the different treatment methods, the length of treatment also exists a certain degree of variability. During orthodontic treatment, it is necessary to maintain the hygiene and care of teeth and braces to avoid excessive growth of bacteria or other harmful microorganisms, which may cause tooth decay, periodontitis and other oral problems.