【摘要】 目的比较3种不同的根管预备方法对根尖封闭性能的影响。方法选取因正畸拔除的人下颌第二双尖牙34颗,单根单管,随机分为3个实验组和2个对照组。对照组每组2颗,实验组每组10颗。分别采用逐步后退法、逐步深入法和冠向下预备技术进行根管预备和冷牙胶侧方加压充填;然后用印度墨汁染料渗透法和透明牙技术进行根尖微渗漏的检测。结果冠向下预备组和逐步深入预备组产生的根尖渗漏小于逐步后退预备组(P<0.05)。结论冠向下预备技术和逐步深入法对根尖封闭性能的影响小于逐步后退法。更多还原

【Abstract】 Objective To evaluate the influence on apical microleakage after three kinds of different instrumentation of the root canals.Methods Thirty-four straight single-root second mandibular premolars were chosen,which were extracted because of orthodontic treatment.The teeth were divided into three test groups and two control groups randomly.There were 10 teeth in each test group and two teeth in each control group.Step-back technique,step-down technique and crown-down technique were used to instrument the root canals of test groups separately.Then lateral condensation technique was used to fill all the root canals.After that,the apical microleakage were tested using Indian ink and transparent teeth technique.Results The apical microleakage with step-down technique and crown-down technique were less than that with step-back technique.It had statistical significant different among the test groups and the control groups(P<0.05).Conclusion The influence on apical microleakage with step-down technique or crown-down technique is less than that with step-back technique.更多还原