Shaping performance of local nickel-titanium rotary file systems on resin blocks

Purpose: The increasing development and clinical adoption of nickel-titanium (NiTi) rotary systems in Türkiye highlights the need for performance comparisons with widely used reference instruments. This study aimed to evaluate the shaping ability of locally manufactured files (EndoPlus Universal Gold-EPUG and EndoArt Action Gold-EAG vs. ProTaper Gold-PTG) in terms of canal transportation, weight loss, and changes in prepared canal area using standardized resin blocks with 30° curvature and 16 mm length.
Methods: Twenty-four blocks with known initial weights were photographed under a stereomicro-scope at 4× magnification, randomly divided into three groups, and prepared with rotary files up to size F2 following each system’s sequence. Irrigation with 2 mL saline was performed after each instrument. Post-instrumentation weights were recorded using a precision balance, while canal transportation at apical, middle, and coronal levels and canal area changes were calculated by superimposing pre- and post-instrumentation images with ImageJ software. Data were analyzed using one-way and two-way ANOVA with Bonferroni post-hoc testing at a 0.05 significance level.
Results: Instrument fractures occurred in one sample from PTG (S2), four from EPUG (three S2, one S1), and two from EAG (S2). No statistically significant differences were found among the groups regarding canal transportation and shaped area changes (p=0.43 and 0.06, respectively). The greatest transportation was observed coronally in all groups (p=0.001). Coronal transportation was significantly higher than apical transportation in the PTG and EAG systems (p=0.001 and p=0.048, respectively). Weight loss was significantly different among all groups (PTG: 3.16±0.45 mg; EPUG: 4.63±0.26 mg; EAG: 5.90±0.63 mg; p=0.001).
Conclusion: Within the limitations of this study, the shaping performance of locally manufactured systems appeared comparable, though further research in extracted human teeth is recommended.

Keywords: Alloys, nickel titanium, root canal preparation.