Effects of rapid maxillary expansion on treatment in class III patients with maxillary protraction

Objective To evaluate the effects of rapid maxillary expansion on treatment in Class Ⅲ patients with maxillary portraction. Methods A total of 54 children with Class Ⅲ malocclusion were selected and divided into two groups. Twenty-six patients (group A) received maxillary protraction without RPE and the other 28 patients (group B) received maxillary protraction combined with RME. Cephalometric radiographs were taken and analyzed before and after treatment.Changes between the two groups were analyzed. Results The trends were similar in ANB, PP-MP,Ptm-A, Co-A, Co-Gn, A-Np, Pog-Np, Pog-NB and Wits value etc. Significant differences in treatment duration, in SN-PP and ANS-Me and in labial inclination of upper incisors were found between the two groups. Conclusions Maxillary protraction combined with or without rapid maxillary expansion was effective in the treatment of Class Ⅲ patients with maxillary deficiency. Key words: Maxillary protraction;  Rapid maxillary expansion;  Class Ⅲ malocclusion