根尖区机用镍钛器械折断的临床治疗体会

目的：探讨机用镍钛器械在根尖区折断的特点及临床治疗经验。方法：收集根尖区机用镍钛器械折断患者18例，记录折断器械的种类，型号，患者的年龄，牙位及其治疗结果。结果：18例折断器械中，发生于前牙3例，前磨牙3例，磨牙12例；其中ProTaper锉11例，Waveone锉5例，Mtwo锉1例,S3锉1例。折断器械成功取出10例，成功率55.6%。其中显微超声技术取出8例，成功率为44.5%；显微镜下加压冲洗法2例，成功率11.1%；保留作为根管充填物5例，旁路通过术2例，显微根尖手术1例。1年根管治疗成功率77.8%。结论：镍钛器械折断好发于磨牙细小根管及复杂根管，折断器械取出的难度大，有效预防器械折断及选择合适的治疗方案是提高根管治疗成功率的关键。

Clinical research of broken Rotary NiTi instruments in lower root canal

Objective:To discuss the characteristics of rotary nickel-titanium(NiTi) instruments fracture in the apical area, and to summary clinic therapeutic experiences.Method:We collected 18 patients, who visited the endodontics department of Huizhou Stomatology from January 2007 to August 2014 due to rotary NiTi instruments fracture in the apical area. Types and mode of the fracture instruments, age of the patients, tooth position, and treatment outcomes were respectively recorded. Analysed the characteristics of instruments fracture and gived the clinical decision. Implemented the plan of remove the sep-aration instruments and evaluate the success rate of root canal therapy. Result:Of the 18 cases with instruments separation, 3 occured in anterior tooth, 3 premolar, 12 molar; 11 Protaper files fractured, 5 Waveone files, 1 Mtwo files, 1 S3 files. The separated fragments were successfully removed in 10 cases, and the total success rate was 55.6%. Microscopic ultrasonic technique were successfully performed in 8 cases with a 44.5%success rate and Technique of washing with pressure under a microscope also in 2 cases with a 11.1% success rate. The separated fragments were keeped in the root canal as the filling material in 5 cases. 2 cases were performed with bypassoperation and 1 case with Microscopic apical surgery. The one year success rate of root canal therapy was 77.8%. Conclusion:The fracture of NiTi instruments frequently occurred in fine and complex root canals in molar. And it is difficult to remove the separation instruments. Thus, it is the key that to effectively avoid the risk of instrument separation and choice the appropriate therapeutic schedule for improving the successful rate root canal therapy.