OBJECTIVE : The aim of this investigation was to analyze the effects of RME and FM on the airway dimensions in Class III patients compared with untreated controls. METHODS : A sample of 47 Class III patients treated with RME and FM was analyzed. The treated group was compared with 18 untreated controls. Lateral cephalograms for each patient at T1, T2, and T3 were digitized. RESULTS : At long-term evaluation a significant increase in airway size and a significant decrease in adenoid size were found in the treated group as well as an improvement in the pharynx dimension. During active treatment the treated group showed a significant improvement in lower airway size and in lower pharynx dimension. A significant decrease in adenoid size was also found. CONCLUSIONS : The treatment with RME and FM produced favorable stable changes in the airway dimensions in Class III subjects when compared with untreated controls.