Objective:The purpose of this studywas to investigate the expression of TGF-B1in the regenerated bone after the operation of the mandibular osteodistraction.Methods:Bilateral mandibular osteotomies were performed in 15 goats. The mandibles were lengthened 10 mm using a custom-made distractorwith a rate of 1 mmPd. 3 goatswere killed respectively atthe end of delayed pe- riod (7 days), and 0, 7, 14 and 28 days after completion of distraction. The distracted callus from all animalswere harvested and processed for immunohistochemical detection of TGF-B1.Results:Staining for TGF-B1was localized in mesenchymal cells of the periosteal region atthe end of delay period. On 0, 7 and 14th day after completion of distraction, a marked increase inTGF-B1ex- pressionwas seen in the regenerated bone, and mainly localized in osteoblasts. On the 28th day after the distraction, TGF-B1 showed weak staining in the distracted callus.Conclusion:TGF-Bappears to play an important role in bone regeneration afterman- dibular osteodistraction.
