Skeletal Stability and Airway Changes After Maxillary Advancement Using a Rigid External Distraction System in Non-Growing Cleft Patients.

Distraction osteogenesis (DO) is a highly effective technique for correction of severe maxillary hypoplasia, especially in patients with orofacial clefts and craniofacial syndromes. The purpose of this retrospective, longitudinal study was to assess long-term airway alterations after maxillary advancement using a rigid external distraction system (RED) in non growing cleft patients. Fifteen cleft patients (8 males and 7 females) aged from 14 to 25 years were included in this study. All of them were treated with a rigid external distraction system for maxillary advancement after a high Le Fort I osteotomy. To analyse airway changes lateral cephalograms were obteined before distraction (T0), immediately after distraction (T1) and 1 to 3 years and 3 months after distraction (T2). All the measurements were describled by means of median, minimum and maximum. In order to evaluate differences between each time interval, a Wilcoxon test associated to a Delta Cliff test was used to evaluate the effect size (level of significance adopted was 5%). A significant maxillary advancement and increased upper airway antero-posterior dimensions were observed after the distraction osteogeness process, as demonstrated by the difference between T1 and T0. No significant relapse at T2 was found. Lower airway and the airway at tip of uvula region did not display significant alterations. A significant maxillary advancement and increased antero-posterior upper airway dimension was measured immediately after maxillary distraction with rigid external distraction in non growing cleft patients. The findings were stable three years after distraction.