五种纤维桩/Panavia F粘接剂/牙本质之间微观机械固位研究

目的通过微拉伸实验和粘接界面的扫描电镜观测,研究五种纤维桩的桩核材料/粘结剂/牙本质之间的微观机械固位强度与形态。方法五种纤维桩：NTI-Kahla Fiber,Twin Luscent Anchors,Tenax Fiber White,PD Tapered Crown Post和Ouya FiberⅠ型。每组10支纤维桩,使用Panavia F粘结至经过常规根管充填和桩核修复根管预备后的下颌前磨牙根管内,其中5个样本扫描电镜下观测纤维桩/粘结剂/牙本质之间结合界面形态,另5个样本进行微拉伸实验,并进行断面观测。结果扫描电镜观测到五种纤维桩的桩核材料/粘结剂/牙本质之间存在相似的微观嵌合形态,微拉伸实验中断裂主要发生在纤维桩材料/粘接剂界面,微拉伸强度值NTI-Kahla Fiber为14.33±5.74Mpa,Twin Luscent Anchors为13.48±8.22Mpa,Tenax Fiber White为13.21±7.54Mpa,PD TaperedCrown Post为12.95±6.57Mpa,Ouya FiberⅠ为13.59±6.31Mpa,各组间无统计差异（P〉0.05）。结论Panavia F树脂粘接剂可以建立与牙本质及纤维桩材料之间的良好连接,五种纤维桩与Panavia F粘结剂及牙本质之间的微观机械固位形态与强度相近。微拉伸断裂模式提示在纤维桩修复中,纤维桩/粘接剂界面是修复体粘接的主要薄弱环节。

Evaluation of micromechanical retention of five types of fiber posts when bonded to tooth dentin with Panavia F luting material

Objective To evaluate micromechanical retention of five types of fiber posts when bonded to tooth dentin with Panavia F luting material through microtensile test and to examine the integration among fiber post, luting material and canal dentin with scanning electron microscope （ SEM ）. Methods Five types of fiber posts （ NTI - Kahla Fiber, Twin Luseent Anchors, Tenax Fiber White, PD Tapered Crown Post, and Ouya Fiber Ⅰ ） were selected for this study. Ten posts in each fiber post group were bonded with Panavia F to the canal dentin of extracted mandibular premolars which were endodontically treated with root canal preparation and filling procedure. Five of these ten specimens in each group were cut perpendicular to their long axis and processed for SEM to investigate the morphology of the post/luting material/canal dentin interface. The remaining 5 specimens in each group were cut to obtain microtensile sticks that were loaded in a universal machine at a cross - head speed of 0. 6mm/min until broken, and the fracture surfaces of the mierobars were examined with steromieroseope as well. The statistical analysis was performed by using two - way ANOVA and the Tukey＇s test for comparison of microtensile bond strength. Results SEM observation showed an interpenetrating adhesion network on the interface of post/luting material/canal dentin in each post group. Most of the Spoeimens were broken between luting material and fiber posts in microtensile test, and there was no significant difference in mierotensile bond strength between each post group （ P 〉 0.05 ）. Conclusion These five types of fiber posts have similar mieromeehanical retention when bonded to tooth dentin with Panavia F luting material. The interface of fiber posts and Panavia F luting material is a weak part, which will possibly influence on the longevity of the whole restoration.