大鼠牙周膜牵张成骨过程中细胞增殖之评价  

Assessment of cell proliferation during distraction osteogenesis of peridental ligament in rats

作　　者：张延晓[1] 周洪[1] 王晓荣[1] 

机构地区：[1]西安交通大学医学院附属口腔医院正畸科,陕西西安710004

出　　处：《上海口腔医学》2011年第2期141-146,共6页Shanghai Journal of Stomatology

基　　金：陕西省科技攻关基金[2007k14-03(2)]~~

摘　　要：目的:通过建立大鼠牙周膜牵张成骨快速牙移动模型,观察牙周膜牵张成骨过程中成骨细胞、破骨细胞及骨细胞的增殖情况。方法:40只SD雄性大鼠,随机分为实验组和正畸模型对照组。所有动物拔除右侧上颌第一磨牙后,对照组按传统方法建立正畸模型;实验组对右侧上颌第二磨牙近中牙槽骨实施减阻措施后,在右侧上颌第二磨牙和支抗牙上安装自制牵张装置,频率为1mm/2d,牵引1周后进入巩固期。所有动物于牵张开始时腹膜内注射溴脱氧尿嘧啶核苷(BrdU),分别在牵张开始后第3、5、10、20、30天,2组动物中随机选择4只动物处死,获取标本后,进行免疫组织化学染色。在标本新生组织中观察BrdU标记细胞的增殖和分化情况,对BrdU阳性细胞进行计数,利用SPSS16.0软件包中的配对t检验等进行统计学分析。结果:实验组的张力侧和压力侧均发现BrdU阳性细胞,主要为骨细胞、成骨细胞、破骨细胞和成纤维细胞等;BrdU阳性成纤维细胞和成骨细胞在第10天达到峰值,破骨细胞于第20天达到峰值,阳性骨细胞的数量随时间变化呈逐渐上升趋势。正畸模型对照组阳性成纤维细胞和成骨细胞在第5天和第10天的表达虽也呈上升趋势,但明显低于实验组,破骨细胞在第5天达到峰值,阳性骨细胞的数量也逐渐增多,但第20天和30天比实验组低。结论:牙周膜牵张成骨的成骨方式主要是膜内成骨;活跃的骨形成发生在牵张结束后巩固阶段的早中期,牙周膜牵张成骨过程中新骨的形成是不断进行的;牙周膜牵张成骨具有更活跃的破骨能力。BrdU阳性细胞能够在牙周膜中存在30d。PURPOSE： To establish an animal model of orthodontic rapid tooth movement through distraction osteogenesis of the periodontal ligament and assess the cell proliferation including osteoblasts,osteoclasts and bone cells.METHODS：Forty rats were randomly divided into experimental and orthodontic control group,and received BrdU injection at the beginning of distraction intraperiotoneally.Traditional orthodontic model was established in the control group.In the experimental group,after some parts of mesial alveolar bone of the upper right second molar grinded,self-made distraction device was installed between the second molar and central incisors,the distraction frequency was 1mm/2d,and after one week,there would be a consolidation phase.Four animals in each group were randomly selected to be sacrificed at 5 time points.After obtaining specimens,immunohistochemical examination was done.Then BrdU labeled cells were observed in the regenerated tissue specimens and the positive cells were counted and analyzed with paired-samples t test by SPSS 16.0 software package.RESULTS： BrdU positive cells were found in both tension and pressure sides,mainly bone cells,osteoblasts,osteoclasts and fibroblasts.BrdU-positive fibroblasts and osteoblasts reached a peak at day 10,and the expression at day 5 and 10 in the experimental group was higher than in the orthodontic treatment group.Osteoclasts reached a peak at day 20,but in the orthodontic treatment group it reached a peak at day 5.The number of positive bone cells was gradually rising over time,but the expression in the orthodontic treatment group was lower than that in the experimental group at day 20 and 30.CONCLUSIONS： Intramembranous ossification is the main pattern during periodontal ligament distraction osteogenesis;Active bone remodeling occurs at the early and middle consolidation,new bone formation is ongoing,and osteoclast activity is more active.BrdU positive cells are able to survive throughout the entire experimental period of 30 days.

关 键 词：牙周膜牵张成骨 牙快速移动 细胞增殖 成骨细胞 破骨细胞 骨细胞 

分 类 号：R783.5[医药卫生—口腔医学]