CAJ | 학술논문

背景：重度弯曲根管的预备是临床根管预备的难点，如预备不当容易出现台阶、根管偏移、根尖孔敞开等并发症，影响根充质量和根尖封闭性，因此选择切削能力和成形能力俱佳的根管预备器械对与弯曲根管预备效果的保证有着重要意义。目的：比较Mtwo、K3机用镍钛器械与不锈钢手动K-file预备磨牙重度弯曲根管的成形效果。方法：将30颗新鲜拔除的人离体上颌第一磨牙重度弯曲近颊根管随机均分为3组，分别采用Mtwo机用镍钛器械、K3机用镍钛器械与不锈钢手动K-file进行根管预备。记录3组根管预备前后根管影像中器械尖端所在位置，测量并比较3组间根管弯曲度的变化、工作长度变化和操作时间。结果与结论：根管预备前，3组根管弯曲度比较差异无显著性意义(P >0.05)；根管预备后，Mtwo机用镍钛器械组、K3机用镍钛器械组根管弯曲度变化小于不锈钢手动K-file组(P <0.01)，Mtwo机用镍钛器械组、K3机用镍钛器械组根管弯曲度变化比较差异无显著性意义(P >0.05)。3组根管预备时间比较差异有显著性意义(P <0.01)，Mtwo机用镍钛器械组最短，不锈钢手动K-file组最长。3组根管预备后根管工作长度改变比较差异无显著性意义(P >0.05)。表明Mtwo与K3机用镍钛器械预备后牙弯曲根管时效率高、成形能力强。
배경：중도만곡근관적예비시림상근관예비적난점，여예비불당용역출현태계、근관편이、근첨공창개등병발증，영향근충질량화근첨봉폐성，인차선택절삭능력화성형능력구가적근관예비기계대여만곡근관예비효과적보증유착중요의의。목적：비교Mtwo、K3궤용얼태기계여불수강수동K-file예비마아중도만곡근관적성형효과。방법：장30과신선발제적인리체상합제일마아중도만곡근협근관수궤균분위3조，분별채용Mtwo궤용얼태기계、K3궤용얼태기계여불수강수동K-file진행근관예비。기록3조근관예비전후근관영상중기계첨단소재위치，측량병비교3조간근관만곡도적변화、공작장도변화화조작시간。결과여결론：근관예비전，3조근관만곡도비교차이무현저성의의(P >0.05)；근관예비후，Mtwo궤용얼태기계조、K3궤용얼태기계조근관만곡도변화소우불수강수동K-file조(P <0.01)，Mtwo궤용얼태기계조、K3궤용얼태기계조근관만곡도변화비교차이무현저성의의(P >0.05)。3조근관예비시간비교차이유현저성의의(P <0.01)，Mtwo궤용얼태기계조최단，불수강수동K-file조최장。3조근관예비후근관공작장도개변비교차이무현저성의의(P >0.05)。표명Mtwo여K3궤용얼태기계예비후아만곡근관시효솔고、성형능력강。
BACKGROUND:Severely curved root canal preparation is the difficulty during clinical root canal preparation, and improper preparation may induce complications such as stage, root canal offset and apical open, which affect the quality of root canal preparation and apical closure. Therefore, it is important to choose a root canal preparation instrument which has the best cutting and forming ability. OBJECTIVE: To compare the shaping ability of Mtwo nickel-titanium rotary instruments, K3 nickel-titanium rotary instruments and stainless steel K-files for the preparation of curved root canals. METHODS:A total of 30 severely curved root canals of freshly extracted human maxilary molars were randomly divided into three groups, with 10 canals in each group. The canals were prepared by Mtwo instruments, K3 instruments and K-files, respectively. The instrument’s tip location in pre- and post-instrumentation radiographs of the three groups was recorded; the changes of root curvature, working length and working time in the three groups were measured and compared. RESULTS AND CONCLUSION:The root curvature showed no significant difference in the three groups before preparation (P> 0.05). The changes of root curvature after root preparation in Mtwo instrument and K3 instrument groups were significantly less than that in K-files group (P < 0.01), and no significant difference was found between Mtwo instrument group and K3 instrument group (P > 0.05). The root canal preparation time in the three groups showed significant differences (P < 0.01), which was the shortest in Mtwo instrument group and the longest in K-files group. The changes of working length after root preparation in the three groups showed no significant difference (P > 0.05). Mtwo nickel-titanium rotary instruments and K3 nickel-titanium rotary instruments are have high efficacy and strong shaping ability in preparing curved root canals.