Is It Possible to Shorten the Jaws Using Contraction Osteogenesis?

Purpose This study investigated whether shortening of osteotomized jaws is possible. Materials and Methods Nine sheep were used (2 as controls and 7 as experimental subjects). Distraction devices that had previously been activated to 10 mm were fixed to the mandibles of all animals bilaterally and used in reverse as a contraction device. Control and experimental animals were sacrificed at 1 month and 3 months. Bone in the area of contraction was evaluated using radiodensitometry and microscopy. Results The mandibles were shortened an average of 5.5 mm. Exaggerated bone formation was seen around the osteotomized cortical bone. When histologic slices from experimental animals were examined 1 month after the contraction period, fibrous pseudoarthrosis formation was seen centrally, with hyaline cartilage around it, whereas normal bone formation was seen in the outer part. The hyaline cartilage had turned into normal bone 3 months after the end of contraction. Conclusions It is possible to shorten bones using contraction osteogenesis.