The role of retainers is to consolidate orthodontic treatment so that the teeth are located in the correct position after orthodontic treatment and do not return to their original position. After orthodontic braces are removed, slowly the teeth may return to the original position, the role of the retainer is to prevent the teeth from returning to the wrong position, generally need to wear a retainer for about half a year, so that the teeth are stabilized in the new alveolar bone position and then remove the retainer to completely complete the entire orthodontic process. Removing the retainer actually only completes half of the orthodontic treatment, only wearing the retainer for a period of time and finally removing the retainer will complete the whole treatment. Retainers have the effect of preventing rebound, it is recommended that patients who want to do or are doing orthodontic treatment should follow the doctor’s instructions and cooperate with the doctor to complete the whole treatment process in order to achieve the best orthodontic results.