直接与间接修复方法对薄弱根管微渗漏影响的研究

摘要:目的 比较同种纤维桩核直接法与间接法修复前牙漏斗状根管之间微渗漏的差异。方法 收集 22 颗上 颌中切牙， 完善根充后， 制备漏斗状根管， 随机分成 A、 B 两组， 每组 11 个试件， A 组直接法完成纤维桩核修复， B 组 采用间接法修复。通过 500 次冷热循环及 240 000 次动态循环加载后， 每组随机抽取 1 件制成切片， 电镜扫描纤维 桩核与牙本质间图像。其余的 20 个试件经过印度墨水染色， 透明化处理后显微镜下对比观察， 记录并分析 2 组微 渗漏的程度及影响因素。结果 300 倍扫描镜下可见 A 组粘结界面处有明显间隙， 且间隙内可见部分杂质， B 组仅 可见粘结界面， 并无明显间隙。体视显微镜下记录 2 组墨水渗漏深度，A 组试件渗漏深度大于 B 组， 差异有统计学 意义 （P < 0.05）。结论 间接法制成的纤维桩核修复前牙漏斗状根管的微渗漏程度显著优于直接法， 具有良好的边 缘封闭作用， 更适合临床应用。

Effects of direct and indirect repair methods on microleakage in weak anterior teeth root canals

Abstract:Objective To compare the difference of the microleakage repaired by direct method and indirect method of the funnel shaped root canal in the anterior teeth. Methods A total of 22 middle teeth at the similar size were collected, prepared into funnel root canal after finishing the root filling. The teeth were divided into A and B groups randomly, and there were 11 test pieces in each group. The root canal was repaired by direct method in group A and indirect method in group B. After 500 thermal- cold cycling and 240 000 dynamic cyclic loading，one tooth was selected in each group randomly. The microstructure were observed by scanning electron microscope (SEM). One piece of each group was randomly selected and the image of the core and the dentin was scanned by electron microscope. The remaining 20 pieces were dyed by India ink, dealt with transparent, compared and observed under the microscope. The degree of microleakage was recorded and analyzed in two groups. Results Under electron microscope, a gap can be observed in the bonding interface of group A. The gap was significantly bigger than that of group B. The leakage was significantly serious in group A than that in group B (P <0.05). Conclusion The level of microleakage of anterior teeth with flared canals, which is restored by fiber post core with the indirect method, is significantly better than that with the direct method. The indirect method has a good edge seal action and is more suitable for clinical application.