In vitro evaluation of the reliability of the Root ZX electronic apex locator

AIM: An experimental comparison of the Root ZX apex locator with the real measurement of the root canal length was carried out using a saline gel to simulate the periodontium. METHODOLOGY: Lengths were taken when the needle reached the 0.5 mark and the Apex mark on the meter. These measurements were then compared with a calculated reference length representing the real length of the root canal. Reliability was assessed using Student's t-test. Precision was assessed using the mean and standard deviation of differences. RESULTS: The Root ZX gave measurements within a range of 0.5 mm in 84.72% of the cases. The intra-operator and inter-operator variabilities were not statistically significant (P > 0.05). CONCLUSIONS: The Root ZX is not capable of detecting the '0.5 mm from the foramen' position and thus, should only be used to detect the foramen (major diameter).