Surgical correction of hemifacial microsomia in the growing child.

This is a follow-up study of 20 children who had surgical correction of hemifacial microsomia in an effort to improve facial growth and minimize secondary distortion. In group 1 (skeletal types I and IIA), 10 children underwent elongation and lengthening of the mandible. In group 2 (skeletal types IIB and III), 10 children had total construction of a new temporomandibular joint and mandibular ramus with rib grafts and costochondral junction. In both groups, an open bite was created on the affected side to provide space for tooth eruption and downward growth of the middle face. The mean follow-up was 50.9 months (18 to 117 months) in group 1 and 45 months (18 to 50 months) in group 2. Analysis of our early results showed that all patients have had downward growth of the midface on the affected side. All five patients in group 1, followed to complete closure of the surgically created open bite, have maintained a level occlusal plane. In group 2, the one patient followed to completion of facial growth continues to have a level occlusal plane and facial symmetry. Appropriately timed mandibular construction and/or elongation in children with hemifacial microsomia is safe and effective. There is a decrease in secondary deformity on the affected side, and the eventual overall facial growth is optimized. Some group 2 children will need secondary elongation and augmentation of the mandible. Nevertheless, this study demonstrates that early mandibular correction may obviate the need for maxillary and orbital procedures in adulthood.