核因子κB受体活化因子配基在人继承恒牙缺失的滞留乳牙及乳牙根生理性吸收不同时期表达研究

Expression of RANKL in permanent teeth germ missing deciduous teeth during different stages of physiological root resorption of human primary teeth

目的研究核因子κB受体活化因子配基(RANKL)在人继承恒牙缺失滞留乳牙及乳牙根生理性吸收不同时期的表达。方法选取2010年6-12月沈阳市口腔医院正畸科及儿童牙病科10～15岁患者因治疗需要拔除的乳牙18颗,按牙根吸收长度不同分为牙根吸收早、中、晚期(早期组、中期组、晚期组),各6颗。同时选取无恒牙胚滞留乳牙(滞留组)和正畸拔除的正常恒牙(对照组)各6颗。采用免疫组化方法检测RANKL蛋白的表达,并测定累积光密度值。结果牙髓成纤维细胞:对照组RANKL累积光密度值明显低于其余组(均P<0.01);早期组、中期组明显低于晚期组(均P<0.01)。成牙本质细胞:对照组RANKL累积光密度值亦明显低于其余组(均P<0.01);早期组、中期组、晚期组三者间差异均有统计学意义(P<0.01)。破牙细胞:对照组未见破牙细胞;早期组、中期组与晚期组比较差异有统计学意义(P<0.01)。结论 RANKL是引起乳牙牙根缓慢吸收的因素之一。

Objective To investigate the expression of RANKL in the permanent teeth germ missing deciduous teeth during different stages of physiological root resorption of human primary teeth. Methods A total of 24 human primary teeth were collected and divided into 4 groups：detained deciduous teeth with missing permanent teeth （ I group）, early stage of deciduous teeth root physiological resorption （ Ⅱ group）, intermediate stage of deciduous teeth root physiological resorption （ m group） and final stage of deciduous teeth root physiological resorption （IV group）. Normal premolars were extracted as the control group, We detected the expression of RANKL by immunohistochemistry technique and Im- age-pro-plus6 image analysis software was used to measure the value of integral optical density（IOD） of odontoclast, fi- broblast in dental pulp and odontoblast stained positively in each group. One-way ANOVA and q-test （a = 0.05） were used to analyze the data statistically. Results Integral optical density of RANKL in fibroblast in dental pulp and odonto- blast were compared in five groups and the value of control group was the lowest. There was significant statistical differ- ence （P 〈 0.01）. As for odontoclast, it didn＇t appear in control group. Other results were the same as odontoblast. Con- clusion RANKL is one of the factors which cause deciduous teeth root resorption.