RESUMO
Distraction osteogenesis has become an alternative technique to treat craniomaxillofacial anomalies. It was initially used to treat mandibular dysplasia and now it is applied to other regions of the craniofacial skeleton. We now present our clinical experience of midface distraction with the use of rigid external distraction for the treatment of an 8-years-old girl with midface hypoplasia in Crouzon's disease, who had undergone fronto-orbital advancement at the age of 6. We performed midface advancement by Le Fort III osteotomy with rigid external distraction system(RED II, KLS Martin, Jacksonville, FL). The active distraction was initiated on the 3rd postoperative day and was continued until the 20th postoperative day for 18 days. The rate of distraction can be adjusted during this time according to clinical judgment and cephalometric assessment. On completion of distraction, the RED II was left in place without activation for 25 days for rigid retention. The RED II was then removed and an orthodontic facemask was applied with elastic traction for 6wks. The total amount of distraction was 18.5mm, 28.5mm, 10.5mm, 14.5mm at right inferior orbital rim, left inferior orbital rim, right intraoral, left intraoral area respectively. The photography, cephalometry, and 3D CT(3 dimensional computed tomography) show that facial convexity was improved. We could correct midface deficiency successfully by LeFort III osteotomy and rigid external distraction.