PURPOSE: The purpose of this study was to compare the clinical and cephalometric post-surgical outcomes of three different types of midface advancement in the growing child: LeFort III advancement with wire fixation, LeFort III advancement with rigid plate fixation, and LeFort III advancement with distraction osteogenesis.

MATERIALS & METHODS: All patients who underwent midface advancement at New York University from 1973 to 2006 were reviewed. A total of 212 patients were identified. Only Crouzon, Apert, or Pfeiffer syndrome patients less than 12 years-of-age with complete pre-operative, post-operative, and 1 year cephalograms were included in the study. A total of 60 patients met the inclusion criteria. A retrospective chart review analyzed operative time, blood loss, hospital stay, complications, and need for additional procedures. Cephalograms were digitized and midface advancement and stability were recorded.

RESULTS: 60 patients underwent LeFort III midface advancement at an average age of 6.0 years. The number of patients, age, sex, and diagnoses were similar for all three groups

The average post-operative horizontal advancement at point A was 10.2 mm in the LeFort III advancement with wire fixation group, 11.2 mm in the plate fixation group, and 15.9 mm in the distraction group. In addition, horizontal advancement at orbitale was 10.3 mm in the wire fixation group, 11.2 mm in the plate fixation group and 12.7 mm in the distraction group. Finally, the horizontal advancement at PNS was 9.7 mm in the wire fixation group, 10.0 mm in the plate fixation group and 13.6 mm in the distraction group.

The average vertical lengthening of the midface at point A was 0.2 mm in the wire group, 3.2 mm in the plate fixation group and 1.1. mm in the distraction group. In addition, the vertical change at orbitale was 0.6 mm in the wire fixation group, 3.4 mm in the plate group, and 2.0 mm in the distraction group. Finally, the average vertical lengthening at PNS was 0 mm in the wire fixation group, 3.1 mm in the plate fixation group and 5.0 mm in the distraction group.

At 1 year follow up, stability in the advancement was seen with a change in position of point A of 0.3 mm in the wire group, 0.8 mm in the plate group and 0.8 mm in the distraction group. Similar stability was seen for all three groups at orbitale and PNS.

CONCLUSIONS: Distraction osteogenesis has provided greater horizontal advancement of the midface following LeFort III osteotomy than has been seen with advancement using wire or plate fixation. The increased horizontal advancement achieved with distraction is stable at 1 year follow up. There is a rotational component to the LeFort III advancement using distraction with point A receiving greater horizontal advancement than orbitale and with PNS undergoing greater inferior displacement. This is likely due to the vector of pull provided by the RED device, which attaches and pulls anteriorly on the maxilla, without a way to prevent downward displacement of the posterior segment.