下颌截骨术对兔颌骨非术区骨改建的影响

Mechanism of Action and Morphologic Changes in the Mandible in Response to Surgery-First Approach: a Rabbit Model

目的 :研究正颌手术对非手术区骨组织改建的影响,以更好地了解正颌手术加速颌骨改建的机制。方法 :12只新西兰大白兔随机分成4组,每组3只,9只行"双下颌骨磨牙区矢状截骨术"为手术组,3只为对照组。手术组9只按处死时间点分为术后1周组、3周组和8周组。每只动物单侧下颌骨用于Micro-CT扫描,对侧下颌骨用于组织学观察。结果:术后下颌骨整个骨组织发生吸收,在术后3周骨丧失最为显著,在术后8周骨形态恢复到近似对照组。下颌骨前牙区(非手术区)在术后1周至3周骨吸收较对照组活跃,表现为骨皮质内血管增生,出现破骨细胞和骨吸收陷窝,在术后3周达到高峰;在术后8周骨组织则与对照组无异。结论:正颌手术后,颌骨先是骨吸收活跃伴破骨细胞增多,骨改建加速,随后新骨生成,骨组织恢复。

Objective： To study the impact of mandibular osteotomy on bone remodeling. Methods： 12 rabbits were randomly and equally divided into 4 groups. Animals in 3 experiment groups were treated by bilateral mandibular osteotomy, the last group was control. The rabbits in experiment groups were sacrificed on 1-week, 3-week, and 8-week respectively. 3 mandible bone of each group were used for Micro-CT scanning, the other 3 mandible bones were used for histological examination. Results： The bone density of the whole mandible had reduced obviously on 3-week, in addition with a higher count of osteoclasts appeared in alveolar bone of incisor region. On 8-week, bone morphology recovered and showed similarity with the control group. Conclusion： Mechanism of regional acceleratory phenomenon may be related to enhancement of osteoclast differentiation and reduction of bone density.