根管壁表面处理和不同粘结系统对纤维桩粘结强度的影响

目的研究不同根管牙本质壁表面处理方法及使用不同粘结系统对石英纤维桩粘结时根管不同部位剪切粘结强度的影响。方法36颗完整离体上中切牙唇侧釉牙骨质界冠方2.0mm处截冠后行根管治疗。专用钻根管预备,酸蚀后,分别采用生理盐水60s(对照组)、10%次氯酸钠(NaOCl)溶液60s、17%乙二胺四乙酸(EDTA)溶液60s与5.25%NaOCl溶液60s联用的根管壁处理方法,结合DUOLINK树脂粘结剂或LUXACORE核材料按析因设计配对行石英纤维桩粘结修复。包埋并切片后,置于MTSSynergie综合测试仪上采用1mm微推出法对不同根管段行剪切粘结实验,记录数值并行统计学分析。结果剪切粘结强度依次为(MPa):6.29±3.77,9.67±3.94,8.07±3.59,2.59±2.04,5.46±3.09,5.80±3.56。10%NaOCl处理组、17%EDTA溶液与5.25%NaOCl溶液联用组剪切粘结强度均明显增强(P<0.0001);DUOLINK树脂粘结剂组剪切粘结强度优于LUXACORE核材料组(P<0.0001);所有实验组中,剪切粘结强度自根管冠方向根方逐渐减弱。结论单独使用10%NaOCl溶液、17%EDTA溶液与5.25%NaOCl溶液联用处理根管壁增强了石英纤维桩修复根管不同部位尤其是根尖的剪切粘结强度。

Effects of radicular dentin treatment and luting materials on bond strength of quartz fiber posts in vitro

Objective To investigate the effects of radicular dentin treatments of sodium hypochlorite（NaOCl） and ethyl acid（EDTA） on the regional root canal bond strengths of quartz fiber posts using 2 luting materials in vitro. Methods 36 intact extracted maxillary central incisors were sectioned perpendicular to the long axis at a point of 2 mm-occlusal to the buccal cement-enamel junction（CEJ） and then endodontically treated. All specimens were randomly divided into 6 groups（n = 6）. Following standardized post space preparations and acid etching, quartz fiber posts（D. T. LIGHT-POST） were placed using three radicular dentin treatments（0.9% NacA for 60 s, 10% NaOCl for 60 s, 17 % EDTA for 60 s followed by 5.25 % NaOC1 for 60 s ） and two luting materials（ ONESTEP / DUOLINK, ONE- STEP / hlxaCore） respectively（factorial design）. Slices with a thickness of （1.00 ±0.05） trim were prepared from the coronal third of each root. The push-out test was performed on different sections of each root at a crosshead speed of 0.5 mm/min. The data were recorded and analyzed（ a = 0.05）. Results A significant difference was found among the groups. 10% NaOCl treatment groups showed higher push-out strengths than that of the control（ P 〈 0.0001）. 17% EDTA followed by 5.25% NaOCl treatment groups showed higher push-out strengths than that of the control（ P 〈 0.001 ）. DUOLINK groups resulted in higher strength than that of composite groups. （ P 〈 0.0001 ）. Bond strengths decreased significantly from coronal to apical root canal regions. Conclusion Within the limitations of this study, micro push-out bond strengths of quartz fiber post can be affected by radicular dentin treatment and luting materials. 10% NaOCl treatment and resin cement combinations resulted in higher bond strength values.