初学者应用两种镍钛机动器械预备树脂弯曲根管的效果比较

目的 比较初学者应用两种机用镍钛器械Protaper和Her0642预备树脂弯曲根管的效果.方法 选取仿制单弯树脂根管32个,15名初学者分别用两种机用镍钛系统Protaper和Her0642进行根管预备,2个仿制单弯树脂根管为阴性对照.分别从推出根尖碎屑量、根尖偏移量及根管弯曲度变化等方面评价两种器械系统的根管预备效果.所有数据均采用SPSS 13.0软件包进行统计学分析.结果 Protaper组预备前后根管弯曲度平均减小6.77°,Hero642组减小5.480°,Protaper组减小根管弯曲度较Hero642组明显.Protaper组成形后的根管宽度均值均大于Hero642组,且根管口、根中1/3成形后的根管宽度差异有统计学意义(P<0.05).此外,根管预备过程中Protaper器械折断3支,Hero642器械折断1支.结论 对于初次使用机用镍钛器械的操作者,尽管Protaper具有良好根管成形的优点,但Hero642系统操作技术简单容易掌握、高效、安全,更适合初学者在临床上使用.

A comparative study of two different rotary nickel-titanium systems in the preparation of simulated resin curved canals performed by abecedarian

Objective To evaluate the shaping effect of two different rotary nickel-titanium instruments in simulated resin curved canals performed by abecedarian.Methods Thirty simulated canals in resin blocks were divided into two experimental groups,and prepared with Protaper and Hero642 by fifteen beginners by crown-down technique.Another two resin blocks were reserved as negative control.Preoperative and postoperative photographs,recorded using a digital camera,were superimposed,and aberrations were recorded.The amounts of apically extruded debris were recorded,the curvature degrees and the apical transportation indexes(ATI)pre-and post instrumentation were compared in order to test the shaping ability of these two instruments.All the data were analyzed with SPSS using t test.Results The result showed that there was no statistically difference in the curvature of the canal reduced by both groups(P>0.05),nevertheless,the curvature was significantly reduced by Protaper than that reduced by Hero642,which was-6.77° with Protaper and-5.48° with Hero642.Three pieces of Protaper with broken,whereas one piece of Hero642 was broken.The mean widths of the root canal prepared by Protaper are larger than Hero642,moreover,the differences of the mean widths in the middle and coronal aspects of the canal are statistically significant.Conclusions Protaper instruments show better shaping ability,however,Hero642 instruments are easier,safer and more efficient to use.Therefore,Hero642 instruments are easier for rotary nickel-titanium instruments beginners to master.