Reconstruction of the Temporomandibular Joint Using a Bone Transport Technique

目的运输牵张成骨技术是一种骨延长技术，用于修复节段性畸形中缺失的骨和软组织。作者探讨了该技术在带内牵引器的TMJ关节成形术中的适用性。材料与方法在42只大白兔(体重3.0 kg)上摘除15 mm升支和TMJ及其盘。术后采用L截骨术，从冠突前缘至下颌骨后缘，应用内牵张矫治器。运送盘每天向前推进0.9 mm，连续14天。另一段24周的时间，在延长完成后已经过去。结果延长完成8周后，X线片上已存在的相邻下颌骨之间的牵张间隙已无法分辨。牵张间隙内可见新生骨和大量软骨。在传输盘的前缘也观察到了新生骨。延长完成8周后，成熟的皮质骨得到重建。在前缘上方形成了一种类似帽子的胶原状结构。这顶帽子可以代替关节盘。结论骨转移技术在TMJ重建中具有较好的应用前景。

Purpose Transport distraction osteogenesis, a kind of bone lengthening, has been used to reconstruct missing bones and soft tissues in a segmental deformity. The authors investigated the applicability of this technique to the arthroplasty of temporomandibular joint (TMJ) with an internal distraction appliance.Materials and Methods A 15 mm ascending ramus and TMJ including its disc was extirpated in 42 white rabbits (3.0 kg weight). After, a L-osteotomy was performed from the anterior border of the coronoid process to the posterior border of the mandible, an internal distraction appliance was applied. The transport disc was advanced 0.9 mm per day for 14 days. Another 24-week period, has passed after the completion of the lengthening. During this period, the rabbits were sacrificed at intervals.Results Eight weeks after the completion of the lengthening, the distraction gap between the adjacent preexisting mandible was indistinguishable in X-ray photographs. New bone and a large amount of cartilage were observed between the distraction gap. The new bone was also observed at the leading edge of the Transport disc. This bone seemed to regenerate froth the surrounding periosteum.More than 8 weeks after the completion of lengthening, the mature cortical bone was reconstructed. A collagenous structure like a cap was formed over the leading edge. This cap may substitute for an articular disc. The new bone has remodeled and resembled the condylar head.Conclusion The bone transport technique is promising for the reconstruction of TMJ.