Accuracy of the initial diameter of finishing files and gutta-percha cones of the ProTaper Universal® system

Abstract

Objective: to assess the accuracy of the nominal initial diameter of ProTaper Universal® finishing files and their respective gutta-percha cones. Method: ProTaper Universal® finishing files, F1, F2, F3, F4 and F5 and corresponding ProTaper cones were used (10 of each). A Profile Projector was used to evaluate the initial diameter of files and cones. All measurements were repeated twice and performed by a single trained operator. A descriptive analysis of the files’ initial diameters was performed considering the tolerance limit established by the ADA number 101. According to this standard, the files F1, F2 and F3 have a tolerance limit of ± 0.025 mm and the files F4 and F5 ± 0.05 mm. The same tolerance limit was used to evaluate the cones. The initial diameters of the instruments and cones studied were compared with the nominal values given by the manufacturer through Student’s T test (pd”0.05). Results: No finishing file group showed adequate accuracy (pd”0.05). Accuracy was verified only from the F5 ProTaper cone group (p> 0.05). It was verified that 30% (n=15) of the finishing files and 20% (n = 10) of the cones exceeded the tolerance limits. Conclusion: Accuracy was not observed for any file and it was identified only in the F5 ProTaper Universal® cone. Most files and cones were within the tolerance limits established by the ADA.