Trans-Sutural Distraction Osteogenesis for Midfacial Hypoplasia in Growing Patients with Cleft Lip and Palate

Background: Although maxillary distraction osteogenesis has been used for early treatment of midfacial hypoplasia, the inevitable osteotomies are still a complicated and invasive procedure for growing patients. Based on the bone-borne trans-sutural distraction osteogenesis, novel improvements to the approach were made to treat midfacial hypoplasia, and the clinical outcomes and skeletal changes were analyzed. Methods: Seventy consecutive growing cleft lip and palate patients with midfacial hypoplasia were treated with trans-sutural distraction osteogenesis. The distraction system consists of a rigid external distractor, nickel-titanium shape memory alloy spring, and bone-borne traction hooks. The whole distraction process was recorded in detail clinically. Lateral cephalographs and computed tomographic scans were taken and analyzed by cephalometric measurement and color-map analysis to assess the skeletal changes. Results: All of the patients except one achieved satisfactory appearance and occlusal relationship. The unilateral maximum traction force presented an increased trend with age, but this relationship was not absolute. The whole trans-sutural distraction osteogenesis process was divided into three clinical stages: the startup period, the rapid movement period, and the consolidation period. Cephalometric analysis showed a great increase in SNA, ANB and horizontal movement of the maxillae after distraction, but with marginal relapse at 6 to 18 months postoperatively. Visualized changes of the midfacial skeleton were observed by three-dimensional color mapping. The results showed an unequal advancement in different regions. Conclusion: Trans-sutural distraction osteogenesis process with adaptations offers an alternative method for the early treatment of midfacial hypoplasia in growing patients with cleft lip and palate. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.