The Precision of Electronic Apex Locators in Working Length Determination: A Systematic Review and Meta-analysis of the Literature.

Introduction: This study aimed to evaluate the precision of electronic apex locators (EALs) in locating the apical constriction (AC) during a root canal treatment compared with a histologic evaluation of the AC as well as the effects of possible influencing factors by means of a systematic review of the literature and meta-analysis.

Methods: A systematic search of the literature was performed to identify studies that histologically evaluated the precision of EALs in human teeth. The identified studies were subject to strict inclusion criteria followed by data extraction and meta-analysis.