Resistance to cyclic fatigue of PathFile, ScoutRaCe and ProGlider glide path files in an S-shaped canal.

AIM: To compare the cyclic fatigue resistance (CFR) of PathFile, ProGlider and ScoutRaCe nickel-titanium (NiTi) rotary instruments used in an S-shaped artificial canal. METHODOLOGY: A total of 90 instruments were tested in an S-shaped artificial canal (n = 30 for each group: PathFile (size 16, 2% constant taper), ProGlider (size 16, variable taper between 2% and 8% along the shaft) and ScoutRaCe (size 15, 2% constant taper). All files were rotated until fracture. The number of cycles to failure was counted to determine CFR. The length of each fractured fragment was measured in millimetres. The CFR was analysed statistically with the Kruskal-Wallis test. The fragment length was analysed using one-way analysis of variance and Tukey's post hoc tests. RESULTS: The ProGlider instruments were associated with significantly greater CFR than the PathFile and ScoutRaCe files in the apical curvature (P < 0.05). There was no significant difference between the CFR of the PathFile and ScoutRaCe files in the apical curvature (P > 0.05). ProGlider, PathFile and ScoutRaCe instruments exhibited similar CFR in the coronal curvature (P > 0.05). CONCLUSIONS: The ProGlider files had greater cyclic fatigue resistance than the PathFile and ScoutRaCe files in the apical curvature of an artificial S-shaped canal.