【作者】 刘畅；

【导师】 刘红；

【作者基本信息】 吉林大学 ， 口腔医学， 2009， 硕士

【摘要】 纤维桩因其优良的物理化学性质,得到了越来越多的应用。如何提高纤维桩的粘结强度成为研究的热点,对牙体硬组织进行适当的处理是获得与树脂良好粘接性能的关键。根管内壁牙本质表面预处理是影响纤维桩粘结强度的重要因素之一。本研究希望通过实验寻找到提高纤维桩粘结强度的根管内壁处理方式,为临床应用提供理论参考依据。本实验将对搜集40颗新鲜无龋的人单根管离体前磨牙,不锈钢K锉逐步后退法预备根管,冷侧压根管充填后进行桩道预备,随机分为8组,采用8种处理方式进行处理。Ⅰ组:20ml 0.9%生理盐水冲洗(对照组);Ⅱ组:5ml 3%双氧水溶液,5ml 5.25%次氯酸钠溶液,10ml 0.9%生理盐水依次冲洗;Ⅲ组:5ml 2%洗必泰溶液,5ml 5.25%次氯酸钠溶液,10ml 0.9%生理盐水依次冲洗;Ⅳ组:5ml 2%洗必泰溶液,5ml 17%EDTA溶液,10ml 0.9%生理盐水依次冲洗;Ⅴ组:5ml 3%双氧水溶液,5ml 17%EDTA溶液,10ml 0.9%生理盐水依次冲洗;Ⅵ组:5ml 5.25%次氯酸钠溶液,5ml 17%EDTA溶液,10ml 0.9%生理盐水依次冲洗;Ⅶ组:35%磷酸凝胶酸蚀30s,10ml 0.9%生理盐水冲洗:Ⅷ组:17%EDTA凝胶处理1min,10ml 0.9%生理盐水冲洗。处理后各组随机取一离体牙,沿牙长轴劈开,取根管内壁较完整者,用场发射环境扫描电镜下观察不同方式处理后的根管内牙本质微观形态,并采用Berg分级法进行评价。之后根据电镜结果进行筛选,除去第Ⅱ组、第Ⅲ组,其余几组牙根用棉捻拭干后,粘结纤维桩。之后用薄片推出实验进行微推出强度的测试。每组随机取出两个已粘接纤维桩的试件用于SEM观察。暴露出完整的根管牙本质-树脂粘接材料-纤维桩的粘接界面。研究结果显示:场发射环境扫描电镜观察到第Ⅳ组～第Ⅷ组均可有效去除桩道预备产生的玷污层。第Ⅳ组、第Ⅶ组纤维桩粘结界面可观察到树脂突的形成。2%洗必泰+17%EDTA冲洗、35%磷酸凝胶酸蚀可显著提高纤维桩在桩道内的微推出强度。桩道深度对纤维桩微推出强度无显著性影响(p＞0.05)。本研究通过对桩道预备后的根管内壁牙本质表面进行不同的方法处理,提高了牙本质-纤维桩的粘结强度,为临床应用提供理论参考依据。更多还原

【Abstract】 Because of their excellent physical and chemical properties, fiber posts have been a growing number of applications. How to improve the bond strength of fiber post has become a hot research. In order to obtain a better bonding strength, we do some appropriate treatment on tooth hard tissue. The preparation of root canal wall dentin surface is one of important factors to influence the bond strength of fiber posts. In this study, we hope to find a method of treatment on the dentin of root canal wall to improve the bonding strength of fiber posts. It can provide a theoretical basis for Clinical applications.The purpose of this study was to evaluate the effect of surface treatment on the retention of glass fiber posts luted with resin cement Solution of chlorhexidine is widely used in root canal irrigation and degermation, and it’s also a broad-spectrum anti-bacterial agent. It can be absorbed by dentinal tubules, and then kills the bacteria directly. It has a better role in killing of both aerobic and anaerobic bacteria. As an irrigation agent, 2%Chlorhexidine is more effective agent against anaerobic bacteria than 5.25% sodium hypochlorite in infected root canals, but it is less toxic and corrosive. 2%Chlorhexidine can also get rid of the restriction of the application of rubber dam. The value of the popularization and application of 2%Chlorhexidine is obviously in the condition of rubber dam has not been universal in our country. Up to now, there were little reports of Chlorhexidine solution apply in preparation of root canal.In this experiment, we collected 20 new extracted non-caries single root canal anterior, Post spaces were prepared in Extracted teeth and then the root canals were subjected to one of the following post-space treatments: (i)water irrigation(control); (ii) irrigation with 3% hydrogen peroxide followed by 5.25%sodium hypochlorite(NaOCl); (iii) irrigation with 2%chlorhexidine solution followed by 5.25%sodium hypochlorite(NaOCl); (iv) irrigation with 2%chlorhexidine solution followed by 17%EDTA solution; (v) irrigation with 3% hydrogen peroxide followed by 17%EDTA solution; (vi) irrigation with 5.25%sodium hypochlorite (NaOCl) followed by 17%EDTA solution; (vii) etching with 35% phosphoric acid-gel for 30s; (viii) 17%EDTA-gel for 1min.The dentin surface s were examined under scanning electron microscopy (SEM) after different post-space treatments. According to the result of scanning electron microscopy examination, we selected six experimental groups of them for next step and observation. Fiber posts were then luted in the treated roots using resin cement with and the thin-slice push-out test was performed. Scanning electron microscopy showed that not all the post-space treatments tested were effective in removal of the smear layer of debris, or sealer / gutta-percharemnants, on the root canal. Group (iv) (v) (vi) (vii) and (viii) were effective. The apical push-out strength was affected by post-space treatment. Both 35%phosphoric acid-gel etching and irrigation with 2%chlorhexidine solution followed by 17%EDTA solution improved the apical push-out strength of the fiber post, with self-etching system. The depth of post space has no influence of apical push-out strength.The result of Chi-square test shows that, there is conspicuous difference. Specimen of the experimental group between the fracture mode was significant difference (p <0.05).The damage of posts did not observed in this experiment.Resin rags of dentin bonding interface were observed in group (iv)and group(vii) by FE-SEM.In order to improve the bonding strength of fiber posts,we did some different treatments of post-space surface in this study,it provids a theoretical basis for clinical applications.更多还原