Multiple segmental gradual distraction of facial skeleton: an experimental study.

The method of distraction osteogenesis was used to move several facial segments in different directions with formation of new bone. On 3 young adult sheep a Le Fort II osteotomy, combined with circumferential orbital osteotomies, was performed. The periosteum over the osteotomies was preserved. Titanium bone screws were placed as bone markers. The segments were fixed with pins and plates to a combined distraction apparatus in order to advance the segments in different directions. By a gradual distraction, the midface was advanced forward by 30 mm. The left orbit was moved laterally 20 mm and the right orbit was moved forward 20 mm. In both orbits there was a concomitant globe movement. New bone formation in the distracted area was obvious radiographically, clinically, and histologically. In conclusion, multiple segmental distraction is possible in the adult sheep face and may offer three-dimensional (3D), controlled correction of complex face deformities.