加速老化对纤维增强树脂桩剪切强度和微结构的影响

目的：研究加速老化对不同品牌纤维增强树脂桩的剪切强度和微结构的影响。方法：将5种纤维桩（Mac-ro-lockTMPost、Luxa Post、Para Post Taper Lux、Ivoclar Vivadent FRC Postec Plus、Nordin Glassix＋plus）随机分为老化组和无老化组并测量剪切强度、显微结构及红外光谱图。采用双因素方差分析老化前后不同品牌样本剪切强度的差异（α=0.05）。结果：各品牌样本老化前后剪切强度差异有统计学意义（P〈0.05）,老化后纤维丝周围附着的基质大部分分离;老化后酯的红外光谱吸光度增加。结论：老化后基质发生了物理老化和氧化反应,交联密度增加,纤维丝/基质界面粘结力减弱并分离,剪切强度降低。

Influence of Accelerated Aging on Shear Bond Strength and Microstructure of Fiber-reinforced Resin Post

Objective：To examine the effects of accelerated aging on shear bond strength and microstucture of different fiber-reinforced resin posts.Methods：Five brands of fiber posts（Macro-lockTM Post,Luxa Post,Para Post Taper Lux,Ivoclar Vivadent FRC Postec Plus,Nordin Glassix ＋ plus） were randomly divided into aging group and no aging group,and then the shear bond strength,the microstructure and FTIR spectra were measured and analysed.The statistical analysis of the difference of shear bond strength was carried out with two-way ANOVA for the samples between the aging and no aging groups（α=0.05）.Results：The shear bond strengths of each group before and after aging were significantly different（P0.05）.Most of the matrix separated from the surface of fiber after aging.FTIR absorbance of ester after aging increased.Conclusion：Physical aging and oxidation reaction took place in matrix,which resulted in an increase of crosslink density in the matrix after aging.Such changes caused interfacial bonds becoming weak and the shear bond strength declined.