9Viteporn S,Mathurasai W.Maxillary features following protraction headgear therapy in skeletal class Ⅲpatients[J].J Dent Assoc Thai,1990,40(4): 148-156.
10Sung SJ,Baik Hs.Assessment of skeletal and dental changes by maxillary protraction[J].Am J Orthod Dentofacial Orthop,1998,114(5):492-502.