A

Because an electronic apex locator relies on an intact apical constriction, its readings become unreliable in immature teeth with a wide-open apex. Studies show that EALs are significantly less accurate in such teeth and should be confirmed with alternative tests, whereas the paper-point moisture technique consistently places the file within ±0.5 mm of the foramen and is recommended for open apices [Kaufman et al., 2024, PMID 39262938; Marcos-Arenal et al., 2009, PMID 19748298].