RESUMEN
AIM: This study investigates the accuracy of an apex locator in mature and immature teeth with divergent root canals ex vivo. MATERIALS AND METHODS: Fifty extracted premolar teeth were utilized for the study, with 25 mature teeth (Nolla stage 9 or 10) and 25 immature teeth (Nolla stages ≤ 8). The discrepancies between the actual length (AL) and the electronic length (EL), measured using a Bingo 1020 apex locator, were compared and analyzed. Statistical analysis included Pearson's correlation analysis, a T-test for independent samples, and multiple linear regression. Statistical significance was set at p < 0.05. RESULTS: The difference between AL and EL in immature teeth was significantly higher than in mature premolar teeth. Nonetheless, patient gender or jaw type (upper/lower) did not affect the accuracy of electronic apex locator (EAL) measurements. CONCLUSION: EAL readings are less accurate in immature teeth than in mature teeth. Supplementary measures, such as radiographic length determination and wet-dry paper point tests, are required to confirm the working length for improved treatment outcomes and patient compliance.