目的

探讨不同截骨方式下镍钛记忆合金牵张器的牵张成骨效果。

方法

选用成年雄性Beagle 犬8 只，双侧下颌骨体制造1.5 cm×1.0 cm 矩形缺损，并在近中形成相应大小的骨传送盘。 左侧骨传送盘行颊舌侧全层截骨术，右侧骨传送盘行保留部分松质骨的皮质切开术，置入镍钛记忆合金牵张器。 于术后1、4、7 d 及9 周拍摄X 线片并进行组织病理学检查，对比双侧牵张区新骨生成情况。

结果

骨皮质切开侧（右侧）牵张区形成新生骨质，传送盘与近中牵张区形成骨性连接，组织学检查符合膜内成骨。 颊舌侧全层截骨侧（左侧）牵张区未见新骨形成，传送盘移位并离开缺损区。

结论

采用保留部分松质骨的骨皮质切开术的截骨方式可成功建立犬下颌骨矩形缺损牵张成骨动物模型。

Objective

To select a suitable osteotomy method for mandibular distraction osteogenesis using TiNi-SMA distractor in mandibular defects of dogs.

Methods

Eight male Beagle canines were enrolled. A 1.5 cm×1.0 cm bone defect was created in both sides of mandible in each dog.Transport bone disc with the same shape was created mesially by osteotomy on left side and corticotomy on right side. TiNi-SMA distractor was settled to perform bone transport to repair defect. Radiographs were taken 1， 4 and 7 days after operation， the canines were sacrificed at 9 weeks after operation for histologcal analysis.

Results

Bone regeneration was formed in distraction zone， and bony connection between the transport disc and mesial mandible was also observed on the right side. The histological appearance was in accordance with intramembranous ossification. On the left side， the transport disc dislocated from the normal mandible and there was no bone regeneration in distraction zone.

Conclusion

The constant force of TiNi-SMA distractor can be used to establish a successfully beagle canine model of mandibular distraction osteogenesis with the corticotomy.