Effects of maxillary distraction osteogenesis on the velopharyngeal configuration of cleft palate patients

To study the effects of internal maxillary distraction osteogenesis(DO) on the velopharyngeal configuration of cleft palate patients.Ten patients with severe maxillary hypoplasia secondary to cleft lip and palate patients (7 males and 3 females, average age 20.1 years old) had undertaken high step LeFort I osteotomy, and internal maxillary distraction devices were applied to advance the maxilla. Before surgery, when DO was completed and 6 months after DO was completed, oriented lateral cephalograms at rest position of each patient were taken, and 6 measure indexes of velopharyngeal configuration were collected and analyzed.All patients had successfully accomplished maxillary DO and the maxilla had been averagely advanced 11.3 mm. PNS-PhW, C-PhW, UL and ANS-PNS-T had all significantly increased, and UD had significantly decreased when DO was completed and 6 months after DO was completed as compared with pre-surgery. No significant linear correlation was found between maxilla advancement distance and velopharyngeal configuration changes.Correction of maxillary hypoplasia secondary to cleft palate surgery by using internal maxillary DO can increase the velopharyngeal cavity depth, and may impair velopharyngeal competence, but the compensatory changes of velopharyngeal soft tissue can alleviate this impairment to certain extent.PubMed06648-513