不同桩核和粘接系统冠向微渗漏的实验研究

A in vitro study of coronal microleakage of different post and cement systems

目的:通过染色法测量冠向微渗漏的大小,比较不同桩核及粘接剂的冠向封闭能力。方法:选择50颗离体下颌单根管前磨牙,使用ProTaper镍钛锉冠向下法进行根管预备。样本随机分为6组。A组为暂封组、B组为树脂粘接纤维桩核组,C组为树脂粘接铸造金属桩核组,D组为磷酸锌粘固铸造金属桩核组,E组为阳性对照组,F组为阴性对照组。除阳性对照组,所有根管侧向加压法充填。桩道预备和桩核修复后印度墨水染色1周,透明处理,体视显微镜下观察冠向染料渗入情况。结果:暂封组冠向微渗漏值明显大于各桩核修复组(P<0.05);树脂粘接的纤维桩组与金属桩组之间无统计学差异(P>0.05);树脂粘接的纤维桩组和金属桩组的冠向微渗漏值均明显小于磷酸锌粘固组(P<0.05)。结论:桩核修复可以减小冠向微渗漏,树脂粘接材料封闭效果更好。

Objective： To compare the coronal sealing abilities of different post and cement systems through measuring the value of leakage by using dye method. Methods.. Fifty human mandibular premolars with single canal were divided into 6 groups randomly. A group ： roots sealed by temporary material, B group ： roots restored with fiber post adhered with composite resin cement, C group ： roots restored with casting metal post and core adhered with composite resin and zinc phosphate cement, D group： positive control, E group： negative control. After finishing preparation and restoration of roots, microleakage was determined by using dye method. Results ： The groups restored with any post and core system produced significantly less mlcroleakage than temporary material sealing group （P 〈 O. 05 ）. But no differences were detected between two groups bonded with the composite resin cement （P 〉 O. 05 ）. Posts adhered with zinc phosphate luting agent produced more leakage than those with composite resin cement（P 〈 O. 05 ）. Conclusion： Luting agent can decrease the coronal microleakage. Composite resin cement provides better sealing ability.