COMPARATIVE EVALUATION OF ELECTRONIC APEX LOCATOR, CONVENTIONAL RADIOGRAPHY, AND RADIOVISIOGRAPHY FOR WORKING LENGTH DETERMINATION: AN IN VITRO STUDY

Abstract

Working length determination (WLD) is one of the most critical steps in endodontics to ensure successful outcomes including efficient cleaning, shaping and obturation of the root canal system and the avoidance of over and under instrumentation. This in vitro study aimed to compare the precision of an electronic apex locator (EAL), conventional intraoral periapical radiography (IOPAR) and radio visiography (RVG) against the actual working length. 93 extracted permanent single-rooted mandibular premolars were evenly split into three groups (n = 31). Standardized access preparation and working length WL measurements were taken and the actual WL was stereo microscopically evaluated after longitudinal sectioning. One way ANOVA and Tukey's post hoc test were used for data analysis. There were considerable differences between the methods (p < 0.001). The electronic apex locator (EAL) gave measurements that were closest to the actual working length AWL and was not statistically substantially different from the reference standard. Both RVG and conventional radiography, on the other hand, significantly overestimated the working length, and there was no significant difference between the two radiographic techniques. With the constraint of this study, the electronic apex locator proved to be more accurate in determining the working length. Nonetheless, radiography techniques have their place in the measurement of root canal morphology and verification of the treatment protocols. Hence, it is advised that the combination of electronic apex locator and radiographic verification is necessary for accurate and predictable endodontic outcome.