Abstract Introduction: Apex locators are used to improve the accuracy of root canal length measurements. Most apex locators operate with batteries but it is not known whether the battery charge level influences the accuracy of the device. The aim of this study was to determine whether different battery charge levels (full, half, and flash modes) would influence the accuracy of working length determination with an apex locator. Methods: Fifty sound single-rooted extracted human teeth were used. After determining the root canal length with a file and a microscope, the canals were measured with three separate Dentaport (DP) ZX apex locators while one of the battery charge level signs (full, half, and flash modes) was showing on the monitor of the device during measurement. Data were analyzed by repeated ANOVA model. Results: The reliability of the measurements during exposure with three different DP ZX apex locators showed that full and half battery charge levels had consistent measurements. However, there was a significant difference in consistency of measurements when the battery charge sign showed the flashing mode (P=0.021). When determining the working length (WL) within ranges of either ±0.5 mm and ± 1 mm, there was no significant difference amongst the various battery charge levels from the WL (P>0.05). However, only the measured means by apex locators with full charge did not show significant difference with the measured length obtained by microscopy (p=0.44). Conclusion: This study demonstrated that the reliability of the DP ZX, and the measured length may be influenced when the battery charge level of the device is flashing.
Masoud Parirokh1 , Hamed Manochehrifar*2 , Roya Borna3 , Arash Shahravan4 , Ali Akbar Haghdoost5 and Paul V. Abbot