根尖周吸收对Rapex5电子根尖定位仪精确性的影响

目的：探讨根尖周吸收对Rapex5电子根尖定位仪（EAL）精确性的影响。方法：根据病史和X线片,选择40例有根尖周吸收的根管为实验组,40例无根尖周吸收的根管作为对照组。用Raypex5测量根管工作长度,与离体直视根尖剖面最狭窄处测得的根管长度进行比较。以距根尖狭窄-0.5～0 mm为准确。结果：实验组根管工作长度的准确率为67.5%,比对照组（90%）明显降低,差异有显著性（P〈0.05）。结论：Raypex5测定根管工作长度的准确率较高,根尖周吸收对其精确性有一定影响。

The effection of periapical resorption on the accuracy of Rapex5 electronic apical locater.

Objective：To evaluate the accuracy of Rapex5 electronic apex locator in determining the working length of the root with periapical resorption.Method：According to history and X-ray,eighty root canals were divided into two groups in this study：forty root canals with periapical resorption were experimental group and forty root canals without periapical resorption were contrast group.The root canal lengths were measured by Raypex5 before extraction,then were measured again after extraction;the results of the 2 measurements were compared.The target interval was set at-0.5 mm to the minor diameter.Result：The degree of accuracy of the experi-mental group was 67.5 %,which was lower than that of the contrast group（90 %）,there was significant difference between two groups（P 0.05）.Conclusion：Raypex5 apex locator is accurate in determination of root canal length,but periapical resorption can affect its accuary.