Abstract: Objective To compare the different effects between micro-implant and MEAW technique on the upper airway dimensions in patients with class III malocclusion. Methods 12 patients were selected to distalize the lower dentition with the micro-implant,while 13 patients were treated with MEAW technique. The cephalometric radiographs of the pre- and post-treatment upper airway in two groups were measured ,then the comparision of those changes was statistically analyzed . Results There were statistically differences in LPW (P<0.05), but other comparison had no statistically significance. Conclusion The LPW is decreased using the micro-implant technique in patients with class III malocclusion.

Key words: Micro-implant, MEAW, upper airway , class III malocclusion