Braces are divided into many types, such as movable braces, fixed braces and invisible braces, etc., as follows: 1, movable braces are generally not replaced, basically only half a year or one year of orthodontic time can be over, at which point the movable aligners can be abandoned; 2, fixed braces are directly glued to the tooth surface, so they can not be replaced regardless of the circumstances; 3, invisible braces are equivalent to a head to tail A series of braces, is given in steps, basically wearing time is 7-10 days, at the request of the doctor 7 days or 10 days to replace the next set of braces. If the invisible braces feel that the power has disappeared after 2-3 days of wear, you will rush to wear the next one, and there is a high risk that the braces will be derailed. If replacement is done too early, it will cause the teeth to move faster than the braces can move, resulting in a derailment and treatment phase failure. If invisible braces are worn for less than 22 hours a day or more, they can be extended as needed, but if they are worn for a longer period of time, the entire orthodontic treatment will be extended.