Description of the disease (onset time, main symptoms, hospital, etc.): I am 23 years old and want to straighten my teeth recently because of work reasons need to go out of town for 3 months I would like to ask how often the bracketless invisible orthodontic technology needs to change the aligners In addition to this orthodontic technology There is a can not be seen with braces and change the aligners once every 2-3 months the technology of the whole teeth. Invisalign generally changes aligners every two weeks, with follow-up appointments every two and a half months, and the doctor will usually hand over five aligners to the patient each time. In addition to this orthodontic technique, lingual braces are the best invisible braces available. In addition, the labial side of the treatment can also choose some ceramic or ice crystal aligners, relatively speaking, also has a certain invisible effect . For longer intervals between visits, it is best to choose bracketless or self-ligating braces with brackets. However, if you are away from home for a long time, local treatment is not recommended. The above are general principles, but they should be considered on a case-by-case basis.