Patients of thin gingiva biotype suffered from gingival recession after orthodontic treatment more frequently, so preventional gingiva graft procedure will be indicated for this kind of patients.

• 牙龈薄的病人在矫正过程中可能有较高牙龈退缩的机会，因此应视情况进行矫正前牙龈移植的预防手术。