Evaluation of the Accuracy of an Endomotor-Integrated Apex Locator Versus a Standalone Electronic Apex Locator in Teeth with Simulated Apical Root Resorption: An In Vitro Study

Objective: This in vitro study aimed to evaluate and compare the accuracy of an endomotor-integrated apex locator system and a conventional electronic apex locator in determining the working length (WL) of root canals with simulated apical root resorption, in both straight and curved canal anatomies. Methods: Sixty-seven extracted mandibular molars with either straight distal canals or curved mesiobuccal canals were included. Simulated external apical resorption was created using a standardized protocol. Actual working length was determined under a stereomicroscope. WL was then measured using an integrated system (EndoRadar Pro) and an electronic apex locator (Dentaport ZX) shaping procedures. The differences between actual and measured WL values were calculated. Data were analyzed using the Kolmogorov-Smirnov test and Chi-square test with a ±0.5 mm tolerance range. Results: All tested devices demonstrated clinically acceptable accuracy within the ±0.5 mm range. In curved canals, the integrated system used with ProGlider showed higher accuracy compared to the systems used with PTN X1 and Dentaport ZX; however, this difference was not statistically significant (Pearson Chi-Square, p = 0.128). In straight canals no statistically significant differences were observed (Pearson Chi-Square, p = 0.155). Conclusions: Both integrated system used with EndoRadar Pro and electronic measurements performed with Dentaport ZX provide reliable measurements for WL determination in the presence of apical root resorption. The integrated system used with ProGlider may offer enhanced accuracy in anatomically complex, curved canals, supporting their clinical use in such challenging scenarios.