Orthodontics is the use of forces within the physiological range to align misaligned teeth to a normal position. Unfortunately, it is not an easy way to find a way to keep a straightened tooth alignment in a stable position all the time. To be fair, every orthodontist encounters cases of relapse after their own treatment, and this is not a pleasant experience for either the patient or the doctor. Many patients find that their teeth are really straight and their bite is good when the orthodontic braces are first removed, but a year or two later they feel that their teeth are not so straight, that the front teeth that were put in are protruding again, and that the extraction gaps may reappear, which is an unpleasant relapse. It is easy for some patients to blame relapse entirely on the doctor until they know what is going on. Let us first understand some general knowledge of the dental and maxillofacial: a person’s teeth from the eruption, to gradually establish occlusal contact to form a complete line of teeth, and then as the age of the tooth surface wear, has been in a dynamic change, and also presents a slow forward movement of the teeth, this trend will not change because of orthodontics; secondly, each person’s tooth alignment is affected by genetics, the more obvious the parents of malocclusion The more pronounced the malocclusion is, the more likely the malocclusion will be passed on to the next generation, and this genetically controlled growth pattern is the potential driving force for the recurrence of malocclusion; the formation of malocclusion is also closely related to individual congenital and environmental influences, such as systemic and local diseases (some developmental syndromes, cleft lip and palate, open mouth breathing, caries, etc.) can affect the development of the bed bone and thus lead to malocclusion, and bad mouth and lip habits are not quit in time. The failure to quit bad oral habits is also a cause of malocclusion. Furthermore, malocclusion is not formed within a short period of time. The long-standing neuromuscular memory and the balance of periodontal ligaments in the original misaligned state become a blocker for the teeth to move to the new position, which is also a key factor causing the recurrence of malocclusion. Therefore, the doctor should try to be accurate in the analysis of the cause of malocclusion, diagnosis, and treatment planning, and then implement specific orthodontic techniques around “how to achieve stable results”, so that the goals of stability, health, function, and aesthetics of orthodontic treatment can be achieved one by one, which is the pursuit of a good orthodontist; for patients For patients, it is wise to recognize the various reasons for relapse and face them frankly, to improve the ability to carry out medical advice during treatment, not to eat too hard food, to keep oral hygiene clean, and to wear long-lasting retainers consciously after treatment.