Electronic apex locator: Principles, Evolution, Comparative analysis, and clinical applications in Endodontics
Keywords:
electronic apex locator, impedance, root canal treatment, working lengthAbstract
Electronic apex locators are devices designed to determine root canal working length by measuring changes in electrical impedance within the canal. Since the initial concept based on electrical circuit principles introduced in 1918, electronic apex locators technology has advanced significantly. Contemporary devices employ multi-frequency alternating current and algorithm-based signal processing to improve accuracy. This review article aims to provide a comprehensive overview of electronic apex locators, including their working principles, generational development, factors affecting measurement accuracy, and recent technological innovations that enhance the efficacy of working length determination in endodontic procedures.
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