【作者】 熊瑛；

【导师】 陈蕾；

【作者基本信息】 中南大学 ， 口腔临床医学， 2010， 硕士

【摘要】 目的通过薄片推出实验分析纤维桩粘接前不同的表面处理对纤维桩粘结强度的影响以及纤维桩在相同的表面处理下,不同深度根管内纤维桩粘结强度的大小,并在此基础上评价纤维桩粘固前的表面处理对牙根抗折裂强度的影响,从而为临床选择合适的表面处理方法提供理论依据。方法第一部分：不同的表面处理对纤维桩粘结强度的影响根据纤维桩不同的表面处理分六组,即硅烷化组、喷砂组、过氧化氢酸蚀组、硅烷化+喷砂组、硅烷化+过氧化氢酸蚀组和未处理组(对照组)。将经过表面处理的纤维桩用树脂粘结材料粘结在离体牙根管内后,模拟口腔环境进行冷热循环和循环加载。将牙根沿与牙长轴垂直的方向切成厚度为1m的薄片,用薄片推出法分别测量并计算根管冠1／3,中1／3和根尖1／3的粘结强度的大小。光学显微镜观察试件破坏方式。第二部分：不同表面处理对纤维桩核冠修复后牙根抗折裂强度的影响将纤维桩分为喷砂组,过氧化氢酸蚀组和未处理组(对照组),在离体牙内粘结后并形成树脂核,金属全冠修复。模拟口腔环境进行冷热循环和循环加载。将试件在电子万能实验机上测试其抗折裂强度,加载头置于全冠颊尖颊斜面中央,加载方向与牙体长轴成30°(模拟下颌前磨牙受力方式),加载速度1mm／min,记录试件破环时的力值及破环形式。结果1.硅烷化组与未处理组的粘结强度无明显差异(P>0.05)2.喷砂组、过氧化氢酸蚀组、硅烷化+喷砂组以及硅烷化+过氧化氢酸蚀组的粘结强度明显大于未处理组(P<0.05)3.硅烷化+喷砂组和硅烷化+过氧化氢酸蚀组的粘结强度明显大于喷砂组和过氧化氢酸蚀组(P<0.05)4.各组根上部粘结强度明显大于根下部(P<0.05)5.喷砂组和过氧化氢酸蚀组的抗折裂强度明显大于未处理组(P<0.05)结论1.单独的硅烷化处理不能提高纤维桩与树脂粘接剂之间的粘结强度。喷砂和过氧化氢酸蚀处理均能提高纤维桩与树脂粘接剂之间的粘结强度和抗折裂强度,可作为纤维桩粘接前的表面处理方法,上述处理后再使用硅烷化处理可进一步提高纤维桩与树脂粘接剂之间的粘结强度。2.桩道的深度会影响粘结强度的大小,根管上部至根尖部位粘结强度逐渐减小。更多还原

【Abstract】 ObjectiveThe purpose of this in-vitro study is to assess the effects of different surface treatments on bond strength of fiber posts to a resin cement through "thin-slice" push out test,compare the bond strength for different regions of the root and evaluate the effects of surface treatments on the fracture resistance of root,so that appropriate surface treatment methods can be used for clinical selection and providing a theoretical basis for improvement bond strength of fiber posts to a resin cement/core materials.Method(1)Effects of surface treatments on bond strength of fiber posts. The fiber posts were divided into six groups according to different surface treatment techniques, including silanization,sandblasting,etching with hydrogen peroxide, sandblasting and silanization, etching with hydrogen peroxide and silanization and no treatment performed.No treatment performed served as the control group. All fiber posts were luted with a composite resin luting agent in the canal roots.After cementation,the roots were subjected to simulated aging conditions consisting of mechanical loading cycles and thermal cycles. The roots were sectioned into slices with 1 mm thickness and a push-out test was performed on three different sections of each root to measure bond strengths. Test piece following testing was placed under optical microscope to observe the breakage method.(2) Effects of surface treatment on the fracture resistance of teeth restored with fiber posts and core system. The fiber posts were divided into three groups according to different surface treatment techniques, including sandblasting,etching with hydrogen peroxide,and no treatment performed.No treatment performed served as the control group. All fiber posts were luted with a composite resin luting agent in the canal roots.The teeth were restored with composite resin cores and metal crowns. After cementation,the teeth were subjected to simulated aging conditions consisting of mechanical loading cycles and thermal cycles. All teeth were loaded in a mechanical testing machine with a compressive load(N) applied at 30 degree to the long axis of the specimen at acrosshead speed of lmm/min until fracture. The fracture load and fracture mode of each teeth were recorded.Results1. No significant difference in bond strength was determined between the silaned and no- treatment groups (P> 0.05).2. Bond strength was significantly greater in the groups performed with surface treatments except the silaned compared with the control group (P< 0.05). 3. Bond strength was significantly greater in the sandblasting and silanization group and etching with hydrogen peroxide and silanization group compared with sandblasting group and etching with hydrogen peroxide group(P< 0.05).4.The coronal third of the root resulted in statistically greater bond strengths than the medium third,whose bond strength was significantly greater than the apical third(P< 0.05).5.The fracture resistance of sandblasting and hydrogen peroxide groups were higher than the the control group.Conclusion1. The use of a silane coupling agent only did not increase the bond strength between fiber posts and a resin cement, sandblasting and etching with hydrogen peroxide can increase the push-out bond strengths of fiber posts and improve the fracture resistance of teeth.2.Bonding was more predictable at the coronal level of the root.更多还原