机用镍钛器械预备弯曲根管的临床应用

目的　研究机用镍钛器械ProFile、ProTaper和Hero 642在弯曲根管预备中的临床应用。方法　选取有弯曲根管的牙髓炎或根尖周炎患牙80颗,分为A、B、C、D 4组,分别用ProFile、ProTaper、Hero 642和不锈钢K锉预备根管,全部患牙均采用侧向加压法充填根管。根据X线片评价根管预备和充填的效果。结果　3种机用镍钛器械均能很好地维持根管的弯曲度和走向,根管的锥度和流畅度佳,无根管偏移、根尖阻塞、台阶形成等并发症发生;术后疼痛发生少且程度轻;ProTaper的操作时间比ProFile和Hero 642短;有2例镍钛器械折断。结论　机用镍钛器械ProFile、ProTaper和Hero 642预备弯曲根管成形效果好,极少有根管内并发症发生,ProTaper比ProFile和Hero 642更快速高效;临床操作中须注意预防器械折断。

Clinical Evaluation of Three Nickel-titanium Rotary Instruments in Preparation of Curved Root Canals

Objective This research aimed to study and assess clinical application of the using of three Nick el-titanium (NiTi) rotary instruments, namely ProFile, ProTaper and Hero 642, in preparation of curved root canals. Methods 80 teeth with curved root canals were instrumented by ProFile, ProTaper or Hero 642 rotary instruments using crown-down technique in test groups and by stainless steel Kfiles in control group. All teeth were obturated with lateral cond ensation method.The efficiency of preparation and obturation was analyzed with radiographs before,during and after operation. Results Three NiTi rotary instruments could keep the curvature and flow of curved canals very well,and the continuously tapered root canal shape was achieved. There were no transportation, apical blockage,and ledge in all test groups. The operati ve time was shorter for ProTaper than that of ProFile and Hero 642. Endodontic flare-up seldom occurred in test groups. Two rotary instruments fractured in cana ls. Conclusion With the NiTi rotary instruments, ProFile,ProTaper and Hero 642,curved root canals can be prepared effectively and quickly. Meanwhile, the problem of instrume nt separation should be prevented.