Electronic Apex Locators and their Implications in Contemporary Clinical Practice: A Review

Background: The apical extent of instrument termination and final root-filling procedures have been found to be key prognostic factors in relation to the outcome of root canal treatment. The precise location of this termination point has always been a challenge in clinical endodontics. Until the introduction of contemporary electronic apex locators (EALs), conventional radiography was traditionally used to determine the working length. Since their inception more than 50 years ago, EALs have drawn a great deal of attention. Objective: The literature pertaining to these devices is saturated yet inexhaustive and controversial. While most reviews try to summarize this topic entirely, the scope of the subject makes this close to impossible. Most systematic reviews report a lack of high-quality evidence, making it impossible to reach a meaningful conclusion. This review of literature focuses on electronic apex location and its accuracy, specifically in relation to variables in the clinical setting that a practitioner might encounter while using this device. Methods: Electronic database searches were undertaken using a combination of key search words to find relevant studies about EALs. Results: The PubMed (MEDLINE) search engine was used to find studies published in the English language with no restrictions for time. Articles that were found to be most pertinent were chosen and included in the review. Conclusion: EALs are indispensable to the practice of endodontics; however, the adjunct use of radiographs remains a reasonable practice.