Variability of the Diameter and Taper of Size #30, 0.04 Nickel-Titanium Rotary Files

Abstract

This investigation examined the variability of tip diameter (D 0) and taper measurements among four different brands of #30, 0.04 nickel-titanium (NiTi) rotary files ( n = 15/brand). With all brands, the mean percent D 0 difference from the manufacturer’s reported (nominal) diameter (Profile GT, 1.73 ± 2.03%; Endo Sequence, 3.38 ± 3.91%; K 3, 4.56 ± 2.36%; Profile, 6.13 ± 4.07%) indicated that files tended to be larger than the nominal diameter. A 1-factor ANOVA and Tukey’s post hoc test revealed a statistically significant difference (p ≤ 0.05) between Profile GT (smallest difference from nominal) and Profile (largest difference). The ANOVA also indicated no significant effect (p > 0.05) of brand on the mean percent difference of the measured taper compared to the nominal taper with the majority of measurements at either 0.039 or 0.040 taper.