Background:Manufacturers have developed numerous nickel-titanium alloys, but there is limited information on the accuracy of integrated Electronic Apex Locators (EAL) when employed in conjunction with various thermal processes for determining the working length. The objective of this study is to employ an integrated EAL and endomotor assembly to evaluate, in an ex vivo setting, the impact of different thermal processes on nickel-titanium instruments.Methods:In this investigation, 40 extracted human maxillary incisors were employed. The visual approach served as the method to determine the control for the working length (WL). The WL was gauged throughout the cleaning and shaping procedures, employing rotary files from the Reciproc, Reciproc Blue, Wave One Gold, Twisted File Adaptive, and Hyflex CM systems, all with a 0.25 diameter instrument size.Results:The precision of the Electronic Apex Locator (EAL) remains unaffected by heat treatment applied to NiTi rotary instruments, as indicated by a lack of significant impact (P > 0.051).Conclusion:The utilization of thermal processes did not influence the accuracy of working length (WL) estimation when employing an Electronic Apex Locator (EAL) integrated with the endomotor.