垂直牵张增高兔下颌牙槽嵴动物模型的建立

The Establishment of an Animal Model of Vertical Distraction Osteogenesis in Rabbit

目的:自制种植型牵张器,增高兔下颌骨验证其成骨效果,为进一步探索牵引成骨的分子生物学机制建立动物模型。方法:日本大耳白兔20只,随机分4组,每组5只,选取一侧下颌牙槽嵴为实验侧,对侧为对照。实验侧于颏孔前矩形截骨,植入一枚种植型骨牵张器,延迟5天后垂直牵张加高牙槽嵴,2次/d,0.5mm/次,共加力牵张4d,分别于牵张后1周、2周、4周、8周处死各组动物,游离下颌骨,大体观察,X线观察,组织学观察。结果:除一枚牵张器松动脱落外,其余牵张器固位稳定牵张成骨效果良好,牙槽嵴平均加高3.26mm,X线及组织学显示,牵张间隙新骨逐渐形成,8周时牵张间隙被成熟新生骨修复。结论:自制种植型牵张器性能良好、体积小、位于骨内,本实验建立了可重复性强、成本低的兔下颌牙槽嵴垂直牵张成骨的动物模型。

Objective： The purpose of this project was to introduce the new type of implant-distraction device and validate the effects of osteogenesis, to investigate the mechanisms of distraction osteogenesis, to build the rabbits model of vertical mandibular alveolar rideg augrnentatior~ Methods： Twenty rabbits, were randomly divide into 4 groups, each group comprising 5 rabbits. A box-shaped osteotomy on the random side of the alveolar bone were carried out and a implant-distraction apparatus was placed. After five days, the alveolar ridge was vertically augmented at the rate of 1.0mm/d and the frequency of 2/d by rotating implant-distraction for 4 days. At the point of 1 week,2 weeks, 4 weeks, 8 weeks of DO, five rabbits were killed, and histological and radiographical evaluations were carried out. Results： During the distraction period, all dental implant-distraction apparatus obtained good healing except one failed for inflammation. The alveolar ridge was vertically augmented 3. 26mm on average. The radiolucency in the distraction site disappeared in 6 weeks. Conclusions： The dental implant-diatraction device in this study have excellent performance in vertical alveolar ridge augmentation with its small bulk. The rabbit model have a characteristic of low cost,and repeatable.