An evaluation of the sagittal upper airway dimension changes following treatment with maxillary protraction appliances

Aims and Objectives: This retrospective study was conducted to investigate the effect of treatment with a maxillary protraction appliance (MPA) on the development of craniofacial structures and the upper airway dimensions. Methods: Twenty patients (10 male and 10 female; mean age 10.3 +/1.12 years) with skeletal Class III malocclusion were included in this study and were evaluated by the use of lateral cephalograms obtained before and after treatment. Treatment changes were determined by means of linear and angular measurements. Results: A significant increase in maxillary forward growth, inhibition of mandibular forward growth, and clockwise rotation of the mandible were observed. The maxillary incisors were significantly proclined and the mandibular incisors significantly retroclined. A multipleregression analysis revealed that maxillary growth had a significant positive effect on the upper-airway dimension. Conclusions: Facilitation of maxillary growth with a maxillary protractionn appliance does contribute to a significant increase in the upper airway dimensions.