两种不同材料K锉预备弯曲根管时对根管壁应力的光弹应力分析  

A photoelastic stress analysis of stresses between the root canal instruments and the root canal wall during preparation of the curved root canal

作　　者：关卿[1] 宋芳[1] 顾永春[1] 呼娜[1] 邓婷婷[1] 倪龙兴[1] 

机构地区：[1]第四军医大学口腔医学院,陕西西安710032

出　　处：《牙体牙髓牙周病学杂志》2011年第3期142-145,共4页Chinese Journal of Conservative Dentistry

摘　　要：目的:分析和比较弯曲根管预备时,两种不同材料K锉与根管壁相互作用力的特点。方法:环氧树脂制作弯曲根管模型20个(弯曲半径5 mm,弯曲度30度)随机平分为2组,分别采用手用不锈钢K锉和手用镍钛K锉按逐步后退法进行根管预备。采用光弹应力分析法比较两种器械对根管壁作用力的大小及分布的差别。结果:#15,#20锉两组产生的平均应力面积(Average Amount of Stress,AAS)无显著差异;#25,#30,#35,#40组间比较,镍钛组在预备弯曲根管产生的AAS显著大于不锈钢锉组。SS组AAS在根管外侧壁明显多于根管内侧壁(P<0.05),NiTi组#25,#30,#35,#40产生的AAS根管外侧壁与内侧壁无显著差异(P<0.05)。结论:在使用#25,#30,#35,#40根管锉预备弯曲根管时,同号的NiTi K锉组对根管壁产生的应力小于SS K锉组。AIM： To analyze the stress produced by stainless steel K file and nickel-titanium K file on the root canal wall during instrumentation of a curved root canal.METHODS： Twenty photoelastic acrylic blocks of curved root canals（radius =5 mm,Schneider＇ angle of curvature = 30 degrees） were prepared and divided randomly into 2 groups.One group was instrumented with stainless steel K files and the other group with nickel-titanium K files,both by the conventional technique.Photoelastic stress analysis was conducted to compare the amount of stress,as demonstrated by Average Amount of Stress（AAS）,produced by stainless steel K file and nickel-titanium K file on the root canal wall.RESULTS： There was statistically significant difference in AAS on the root canal wall between #25,#30,#35 and #40 stainless steel K file group and nickel-titanium K file group.One finding of our study was that the stainless steel K file group demonstrated more stress on the outer than the inner canal curvature,while in the nickel-titanium K files group,there was no significant difference between the outer and the inner canal curvature.CONCLUSIONS： The #25、#30、#35、#40 NiTi K files showed less stress on root canal walls than their cerresponding stainless steel K files.

关 键 词：弯曲根管 环氧树脂 光弹应力分析 

分 类 号：R783.1[医药卫生—口腔医学]