1. Correctors who need surgical treatment. Due to congenital or acquired factors, some orthodontists have deformities in their teeth and jaws, and some deformities can be improved and treated by simple orthodontic methods. However, some types of orthodontics require surgical treatment. In this case, invisible braces can't be fully used, and invisible braces can only be used as an auxiliary tool, otherwise the expected effect of rectification will be greatly reduced.

2. cooperate with doctors to correct the degree of correction is not high. As we all know, invisible braces can wear it himself, which is good for oral health. However, some orthodontists do not pay enough attention to the doctor's advice, such as not wearing braces on time, often not wearing braces, which is easy to fall off, and orthodontists require orthodontists to wear braces for a long time, which is not conducive to better orthodontics.

3. The dental problem is more complicated. Everyone's dental problems are different, but the ultimate goal is to solve the dental problems. However, some orthodontists have complex dental problems, such as complex malocclusion. For orthodontists with this kind of dental problem, it is difficult to achieve the best orthodontic effect by using invisible braces, and even it is difficult to effectively adjust the relationship between jaws.