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目的对比评价三种根管充填技术的根尖封闭能力。方法收集2011年10月至2012年5月中国医科大学附属口腔医院口腔颌面外科门诊因正畸或牙周病拔除的新鲜离体单根管牙34颗，根管清理后用机用ProTaDer镍钛锉经Crown—Down技术预备，然后随机分为A、B、C三组。A组（11颗）采用冷牙胶侧方加压充填技术充填根管，B组（10颗）采用超声侧方加压充填技术充填根管，c组（13颗）采用连续波热牙胶垂直充填技术充填根管。所有实验牙均使用AHPlus根充糊剂。根管充填后的各组实验牙采用染料渗透法检测根尖微渗漏的发生情况，体式显微镜下测量自根尖孔向冠方的染料渗透长度，采用SPSS11．5统计软件包对测量数据进行分析。结果A组与B、c组的根尖微渗漏数值间差异有统计学意义（P〈0．05），B组与c组的根尖微渗漏数值间差异无统计学意义（P〉0．05）。结论超声侧方加压充填技术和连续波热牙胶垂直充填技术的根管封闭能力优于冷牙胶侧方加压技术，而前两种充填技术的根管封闭能力无明显差别。

Comparative study of the apical sealing ability of three canal obturation techniques

Objective To compare and evaluate the sealing ability of three canal obturation methods. Methods Thir- ty-four single-canal extracted teeth were cleaned the root canal and shaped using the Pro-Taper Ni-Ti rotary instru- ments with the Crown-Down technique. All teeth were randomly divided into three groups：Group A （11 teeth） were ob- turated with the cold lateral condensation technique;Group B （10 teeth） were obturated with the ultrasonic lateral con- densation technique;Group C （13 teeth） were obturated with the continuous-wave of gutta-percha vertical condensation technique. All the teeth were given the same sealer （AHPlus）.The leaked condition of the apical was measured by dye in- filtration test. Linear dye penetration was measured under stereo microscope with calibrated eye piece from the apical to crown of the teeth, and the results analyzed. All measurements were analyzed by SPSSll.5 software. Results The length of apical dye penetration showed significant difference between Group A and B and between Group A and C（P 〈 0.01 ）. There was no significant difference between Group B and C （P 〉 0.05）. Conclusion The ultrasonic lateral con- densation technique and the continuous-wave of gutta-percha vertical condensation technique are better than the cold lateral condensation technique with gutta-percha, and the first two root canal filling techniques have no significant differ- ence in sealing ability.