大鼠正畸牙根吸收早期龈沟液中DPP的变化规律

Dentin phosphoprotein in gingival crevicular fluid during early orthodontic root resorption in rats.

目的:构建大鼠正畸牙根吸收模型,检测龈沟液中牙本质磷蛋白(DPP)的浓度变化规律。方法:雌性12周龄SD大鼠46只,其中16只取上颌第一磨牙及牙周组织,通过HE和TRAP染色观察不同时间点根吸收程度;另30只随机分为2组,持续加力28 d(CF组)和加力14 d后停止加力(IF组),收集龈沟液并通过ELISA检测DPP浓度。结果:持续加力14 d,DPP浓度逐渐升高,CF组与IF组间无显著差异(P>0.05);第14 d到28 d,CF组DPP浓度逐渐降低,而IF组DPP浓度在第21 d仍升高,组间有显著差异(P<0.01)。根吸收相对面积和DPP浓度显著相关(P<0.05)。结论:DPP作为牙的特异性蛋白,与正畸牙根吸收的修复相关,可能是早期诊断正畸牙根吸收的指标。

Objective：This study aimed to establish the animal model of early orthodontic root resorption in rats,and determine whether dentin phosphoprotein（DPP） in gingival crevicular fluid（GFC） could serve as a prognostic factor for orthodontic root resorption.Method：46 12-week-old female SD rats were selected.The maxillary left first molar was drawn medially by applying an excess force.16 rats were killed and the sections were treated with HE and TRAP histochemistry in the aim of observing the root resorption.The other 30 rats were randomly divided into continuous force group（CF） and the force suspended group（IF） and GFC was collected.The concentrasion of DPP were assayed by using the biochemistry techniques of ELISA.Result：From 0d to 14d afterburner,concentration of DPP gradually increased,there were no significant differences between the two groups（P 0.05）;from 14 d to 28 d,the concentration of DPP decreased in CF group,while it remained elevated on the 21th day,then reduced a little in IF group.The data between the two groups was statistically significant difference（P 0.01）.The relative area of root resorption was correlated to the concentration of DPP,and the Pearson correlation coefficient was 0.618（P 0.05）.Conclusion：DPP in GCF could be suitable biological marker for monitoring root resorption.