Effects of Bone Anchored Maxillary Protraction Protocols on Sagittal Airway Dimensions

Objectives: The aim of this study was to evaluate the effects of two protocols of bone anchored maxillary protraction on the sagittal nasopharyngeal airway dimensions in growing subjects with Class III malocclusion and maxillary deficiency when compared with an untreated Class III control group.
Methods: Methods: Thirty growing Class III subjects with maxillary deficiency in the late mixed or early permanent dentition phase were included in the study. In Group 1 (n=10) skeletally anchored facemasks were employed with miniplates placed at the zygomatic buttress. In Group 2 (n=10) patients were treated with Class III elastics extending from infrazygomatic miniplates in the maxilla to symphyseal miniplates in the mandible. Group 3 (n=10) was an untreated control group. Pre and post treatment cephalometric radiographs were analyzed.
Results: Results: The treatment periods were 8 and 8.9 months in Groups 1 and 2, respectively, and the untreated control group was observed for 9.4 months. The maxilla protracted forward significantly in Groups 1 and 2 when compared to the untreated control group (4.87 mm in Group 1 and 5.81 mm in Group 2); overjet and upper incisors display were improved without proclination or mesialization of the maxillary teeth relative to the maxillary base. Treatment changes revealed significant increases in the sagittal dimensions of the nasopharyngeal airway in the both treatment Groups 1 and 2 when compared to the untreated control group.
Conclusions: Conclusions:
The two skeletal anchorage protocols for maxillary protraction effectively resolve severe maxillary deficiently in growing Class III patients. In addition the nasopharyngeal airway dimensions were increased after the treatment.