BACKGROUND: In traditional Le Fort III distraction, the transport segment is advanced en bloc without addressing differences in the relative retrusion of the facial structure. The authors describe three methods for correcting these asymmetries with differential facial advancement. METHODS: Eight patients (age range, 4 to 20 years) with asymmetric facial hypoplasia were treated by Le Fort III midface distraction using an external device. Two patients with nasal bone hypoplasia exceeding midface retrusion were treated with nasal passenger grafts at the time of osteotomy. Two patients with asymmetric rotational midface deformities underwent wire cerclage swing advancement of the affected side to achieve differential advancement. Four patients with central nasomaxillary retrusion exceeding zygomatic retrusion underwent segmental Le Fort III osteotomy with simultaneous zygoma repositioning and Le Fort II distraction. RESULTS: Differential midface advancement was achieved in all patients. Midface distraction and nasal passenger grafts resolved obstructive sleep apnea, improved globe protection, and improved fit of prescription glasses. After Le Fort III swing advancement, the centric relation and malar asymmetry were corrected with differential advances of 10 and 15 mm compared with the unaffected side. In the segmental osteotomy Le Fort III group, the central face was distracted independently of the zygoma repositioning, thus correcting the shortened retruded central midface without distorting the orbitomalar relationship and improving airway obstruction, anterior open bite, short nose, and proptosis. CONCLUSIONS: Midface distraction techniques have evolved to include the principles of segmentation, graft augmentation, and controlled rotation. The benefits of gradual distraction can be realized without compromising the aesthetic and functional result.
BACKGROUND: In traditional Le Fort III distraction, the transport segment is advanced en bloc without addressing differences in the relative retrusion of the facial structure. The authors describe three methods for correcting these asymmetries with differential facial advancement. METHODS: Eight patients (age range, 4 to 20 years) with asymmetric facial hypoplasia were treated by Le Fort III midface distraction using an external device. Two patients with nasal bone hypoplasia exceeding midface retrusion were treated with nasal passenger grafts at the time of osteotomy. Two patients with asymmetric rotational midface deformities underwent wire cerclage swing advancement of the affected side to achieve differential advancement. Four patients with central nasomaxillary retrusion exceeding zygomatic retrusion underwent segmental Le Fort III osteotomy with simultaneous zygoma repositioning and Le Fort II distraction. RESULTS: Differential midface advancement was achieved in all patients. Midface distraction and nasal passenger grafts resolved obstructive sleep apnea, improved globe protection, and improved fit of prescription glasses. After Le Fort III swing advancement, the centric relation and malar asymmetry were corrected with differential advances of 10 and 15 mm compared with the unaffected side. In the segmental osteotomy Le Fort III group, the central face was distracted independently of the zygoma repositioning, thus correcting the shortened retruded central midface without distorting the orbitomalar relationship and improving airway obstruction, anterior open bite, short nose, and proptosis. CONCLUSIONS: Midface distraction techniques have evolved to include the principles of segmentation, graft augmentation, and controlled rotation. The benefits of gradual distraction can be realized without compromising the aesthetic and functional result.