临床根管预备对电子根尖定位仪精确性影响的研究

Influence of root canal preparation on fidelity of electronic apical locator (EAL) in clinical application

目的探讨根管预备对电子根尖定位仪(Electronic Apical Locator,EAL)精确性的影响。方法采用数字随机法把根管分为4组:初尖锉组:使用初尖锉取得手感法的根管工作长度并使用EALs(Root ZXand Raypex-5)测量根管工作长度;②扩一组:比初尖锉大1号的锉预备根管并使用EALs测量根管工作长度;③扩二组:扩至比初尖锉大2号的锉并用EALs测得根管工作长度;④扩三组:扩至比初尖锉大3号的锉并用EALs测得根管工作长度。将各组测量值与拔牙后直视状态下测得的根管长度进行比较。结果初尖锉组测量根管工作长度的准确率为:手感法55%,Root ZX85%,Raypex-590%;扩一组、扩二组和扩三组依次分别为:Root ZX90%、90%、95%,Raypex-595%、100%、100%。结论电测法测定根管工作长度准确率高,临床根管预备不会降低EAL的精确性。

Objectives To explore the influence of root canal preparation on fidelity of electronic apical locator （EAL） in clinical application. Methods The root canals were divided into four groups randomly： （1）The group of first files root canal working lengths were measured with the first files by handing method,Root ZX and Raypex-5.（2）The group of enlarged to one size than the first files to preparate root canals with files being enlarged to one size than the first files and measure their working lengths by the EALs. （3） The group of enlarged to two size than the first files to preparate ordinally with files being enlarged to one size and two sizes than the first files and measured by the EALs. （4） The group of enlarged to three sizes than the first files to preparate ordinally with files being enlarged to one size, two sizes and three sizes than the first files and measure. And then every group＇ s root canal working length was compared with the length measured from extracted teeth on euthyphoria. Results In group of first files, the accuracy rates of root canal working lengths measured by handing method, Rooot ZX and Raypex-5 were 55% ,85% and 90%. In groups of enlarged to one sizes, two sizes and three size than the first files, the accuracy rates by Rooot ZX were 90%,90% and 95 %, while those for Raypex-5 were 95 %, 100% and 100%. Conclusion EAL has higher accuracy, and clinical root canal preparation wouldn＇ t lower its fidelity.