中文摘要：

目的 研究正畸力作用下白介素17 （interleukin-17,IL-17）在不同状态牙周组织中的表达变化,探讨牙周炎正畸治疗机制.方法 77只6周龄SD大鼠按随机数字表法分为3个移动组（正常、牙周炎活动期和牙周炎恢复期移动组,每组21只）和2个对照组（牙周炎和空白对照组,每组7只）.各牙周炎组大鼠采用结扎＋涂易感菌＋糖水喂养建立牙周炎活动期模型,牙周炎恢复期移动组建模后去除上述刺激因素并行牙周治疗,进入牙周炎恢复期.处死2个对照组大鼠,并用镍钛拉簧以0.49 N力近中移动各移动组大鼠上颌第一磨牙,并分别于移动后第3、7和14天处死（每组每个时间点7只）.免疫组化检测牙周组织IL-17表达.实时定量PCR检测IL-17 mRNA表达.结果 免疫组化显示,与空白对照组相比,牙周炎对照组及3个移动组各检测时间点牙周组织IL-17均呈强阳性表达.实时定量PCR显示,除正常移动组和牙周炎恢复期移动组第14天IL-17 mRNA表达量（1.00±0.07和1.19±0.15）与空白对照组（1.00±0.00）差异无统计学意义外（P＞0.05）,其余各组各时间点IL-17mRNA表达量均显著高于空白对照组（P＜0.05）.牙周炎恢复期移动组第3和7天IL-17 mRNA表达较同时间点正常移动组显著增高、较同时间点牙周炎活动期移动组显著减小（P＜0.05）.结论 IL-17参与调节正常及牙周炎正畸牙齿移动.相对于正常牙周,牙周炎恢复期正畸力在初期更易增加IL-17的表达,IL-17于加力后期可恢复正常.而牙周炎活动期施加正畸力可使IL-17始终维持较高水平.

英文摘要：

Objective To investigate interleukin （IL）-17 expression induced by orthodontic force in periodontal ligament under different periodontal conditions.Methods Seventy-seven male SD rats were divided randomly into 5 groups：healthy movement group （HM）,active periodontitis movement group （PM） recovery periodontitis movement group （RM）,positive control group （PC） and normal control group （NC）.Active periodontitis was set up by means of ligature＋susceptible bacteria＋suger water in PM,PC and RM groups.This stimulating factor was removed in RM group.NiTi spring was used to apply 0.49 N mesial force to move upper first molar of the rats in HM,PM and RM groups.HM,PM and RM group rats were sacrificed on day 3 （d3）,day 7 （d7） and day 14 （d14）.Expression changes of IL-17 in periodontal tissue in each group were measured using immunohistochemical stain and real time fluorescence quantitative PCR.Results IL-17 expression in periodontal ligament showed more positively in PM and RM groups compared with NC,PC and HM groups.No difference was found in the expression of IL-17 mRNA in NC （1.00±0.00） （P〉0.05）,except in HM d14 （1.00±0.07） and RM d14 （1.19±0.15）.Higher expression of IL-17 mRNA （P〈0.05） was found in other groups.The expression of IL-17 mRNA in RM d3 and d7 increased more than that in HM group in the same period （P〈0.05） and it decreased significantly （P〈0.05） compared with that in PM groups in the same period.Conclusions IL-17 was involved in the regulation of orthodontic tooth movement in different periodontal conditions.Orthodontic force caused limited increase of IL-17 mRNA expression in recovery phase of periodontitis at early stage,then back to normal.However,in active inflammatory periodontal tissue,orthodontic force kept IL-17 mRNA at high level.