大鼠前牙移动后保持过程中OPG在牙周组织压力侧的表达及作用

Expression and Significance of OPG in the Periodontium on the Pressure Side During Retention Stage After Anterior Tooth Movement in Rats

目的研究大鼠前牙保持阶段,压力侧牙周膜中OPG的表达,探讨OPG在大鼠前牙正畸后保持阶段对牙周组织改建中的作用,分析大鼠前牙加力后最短保持时间,推测临床正畸治疗后最短保持时间。方法选择雄性SD大鼠36只,随机分为6组,空白对照组及试验组5组,按保持时间长短,分别为保持1、3、7、14及21 d组,每组6只。试验组在建立大鼠保持期模型后,按分组要求处死大鼠,空白对照组则同条件饲养7 d后直接处死。用免疫组化法分析大鼠前牙牙周膜压力侧OPG的表达。结果保持1、3、7 d组OPG表达呈5时间依赖性且表现为下降趋势,保持14、21 d组与空白对照组相比,差异无统计学意义(P<0.05)。结论 OPG参与保持期大鼠前牙牙周膜压力侧的骨改建,并与保持时间呈重度相关,推测保持约14 d后牙周组织压力侧骨改建基本完成。

Objective The present study was carried out to investigate the expression of OPG in the pericementum on the pressure side of anterior teeth during retention stage in rats,and to explore the significance of OPG on periodontal reconstruction in the period of retention after orthodontic treatment of anterior teeth in rats,so as to analyze the shortest retention time of rat anterior teeth after applying force,and to predict the shortest retention time after orthodontic treatment in clinical.Methods A total of 36 male SD rats were selected and randomly divided into 6 groups of a blank control group and 5 experimental groups,with 6 rats in each group.The latter 5 experimental groups were sub-grouped according to the length of retention,including 1-day retention group,3-day retention group,7-day retention group,14-day retention group and 21-day re-tention group.After the establishment of rats model during retention stage,rats in the experimental groups were sacrificed in accordance with grouping requirements.Furthermore,rats in the blank control group were put to death directly following 7 days of feeding under the same condition.Immunohistochemistry was utilized to mea-sure the expression of OPG in the pericementum on the pressure side of anterior teeth in rats.Results OPG ex-pression showed a time-dependent decrease in the 1-day retention group,3-day retention group and 7-day retention group.However,there was no significant statistical difference in the comparison of the 14-day reten-tion group and the 21-day retention group with the blank control group(P<0.05).Conclusion OPG is in-volved in bone remodeling of the pericementum on the pressure side of anterior teeth during retention stage in rats,and presents a high correlation with the retention time.Bone remodeling of the periodontium on the pres-sure side is speculated to be completed basically after retention for about 14 days.