A novel osteogenic distraction device for the transversal correction of temporozygomatic hypoplasia

Hemifacial microsomia (HFM) is a congenital disorder characterized by craniofacial malformation of one or both sides of the lower face. Since these anomalies are associated with soft-tissue deficiencies, corrective surgery is often difficult. Bone grafts have typically been used for augmentation, but distraction osteogenesis now offers an alternative for many craniofacial deficiencies, but there are few if any appropriate distraction devices and surgical procedures for the augmentation of craniofacial transversal dimensions.

The aim of this study was to evaluate a technique for guided augmentation of craniofacial transversal dimensions through distraction osteogenesis. We tested the efficacy of a prototype distractor, developed in collaboration with Medartis, using cadavers and demonstrated its application for the correction of the transverse dimension of the temporozygomatic region in a patient with Goldenhar syndrome.

CT scans showed a 4-mm transverse augmentation of the bony surface after 9 days and a 10-mm increase after 30 days. Upon removal of the distractor (60 days after the first surgery) CT indicated good bony fusion and a stable result in the transverse plane. Six months after removal of the distractor, 3D computed tomography confirmed the success of the transverse augmentation, as it appeared to be stable and reliable.

Distraction osteogenesis, using our device, can be used to correct the transverse dimension of the temporozygomatic region in HFM patients. It should also be considered for the correction of residual postsurgical skeletal deficiency due to surgical relapse or deficient growth, and unsatisfactory skeletal contour.