This dataset and documentation present a novel ex-vivo model for simulating root canal length determination using an electronic apex locator. Extracted teeth were embedded in a plastic tube filled with 9% sodium chloride solution up to the cervical level. Canal lengths were measured with the Endo E Plus apex locator in both 0.5 mm and Apex modes. Measurements were confirmed under magnification, revealing extremely accurate results. The purpose of this study is to offer a reproducible, safe, and low-cost method for educational use and device calibration. All teeth used had been preserved dry for several years. This is an original technique that has not been documented in previous literature.