Effect of different kinematics and perforation diameter on integrated electronic apex locator accuracy in detecting root canal perforations

Abstract

This study aimed to evaluate the precision and reliability of the integrated electronic apex locator in determining various root perforation diameters and to examine the impact of instrumentation kinematics on perforation site detection. One hundred extracted single-root mandibular premolars were artificially perforated at five distinct diameters (0.25–1.25 mm), located 5 mm above the root apex. The teeth were then divided into 10 groups based on perforation size and kinematic subgroup (rotary, reciprocation; n = 10/subgroup). Actual distances to the perforation site (actual length) were measured under a dental operating microscope. Electronic distances (electronic length) were determined using an endodontic motor with an integrated electronic apex locator using rotary or reciprocating instrumentation kinematics during root canal treatment. To quantify the actual length to the electronic length discrepancies, individual tooth measurements were compared. The integrated electronic apex locator failed to identify perforations ≤ 0.50 mm in diameter. Electronic length measurements were similarly accurate for 1.00 and 1.25 mm perforations but more precise than for 0.75 mm perforations. Instrumentation kinematics did not affect the electronic length measurement accuracy. Integrated electronic apex locators failed to detect small perforations during root canal treatment. The perforation diameter influenced the detection accuracy of integrated electronic apex locators, whereas kinematics had no effect.