Ex vivo evaluation of the accuracy of four electronic foraminal locators

To evaluate the accuracy of four different Electronic Foraminal Locators (EFLs): Root ZX II (J. Morita, Tokyo, Japan), Romiapex A15 (Romidan, Kiryat-Ono, Israel), FinePex (Schuster, Porto Alegre, Brazil), and VDW Gold (VDW, Munich, Germany), in determining root canal length.

Twenty-seven human single-rooted teeth had their crowns sectioned at the cementoenamel junction, and the actual length of the tooth was obtained by visualizing with an operative microscope a #15 file placed adjacent to the apical foramen. The teeth were instrumented with R25 and R40 files, and at the end of each instrumentation, measurements of the lengths of the root canals were made with #25 and #40 files. The data were statistically analyzed by ANOVA and chi-square tests and were considered significant when P<0.05. All devices showed a tendency to underestimate measurements by 0.25 mm diameter.

The mean accuracy of the Root ZX II appliance was statistically lower than the other EFLs (P<0.001). For the 0.40 mm diameter, the mean accuracy of the Romiapex A15 appliance was statistically higher than the other LEFs (P<0.001). However, when the diameter was 0.40 mm, only the Romiapex A15 device tended to overmeasure. Regarding the acceptable limits of variation, it was observed that the devices showed similar efficiency in determining odontometry (P>0.05), both with diameters of 0.25 mm and 0.40 mm.

It was concluded that the devices presented similar and adequate efficacy when observing the limits of acceptable measurements. It was observed that increasing the apical diameter did not influence the accuracy of EFLs in determining root canal lengths. Key words:Endodontics, working length, electronic foraminal locators, endodontic treatment.