Abstract
BACKGROUND: This study presents a novel numerical evaluation of the bending and torsion behavior of four nickel-titanium glide path instruments, addressing a critical gap in understanding their mechanical performance under clinical conditions. MATERIAL AND METHODS: The evaluated instruments include the WaveOne Gold Glider with a parallelogram cross-section, the R-Pilot with an S-shaped cross-section, the ProGlider with a square cross-section, and the V Taper 2H with a triangular cross-section. Using advanced computer-aided design (CAD) software, detailed geometric models of each instrument were created, followed by numerical simulations performed in the SolidWorks finite element platform. Material properties of nickel-titanium alloys and boundary conditions were defined based on ISO 3630-1 specifications for bending and torsion tests. RESULTS: The findings revealed significant variations in stress distribution and flexibility among the instruments. Notably, the R-Pilot demonstrated superior flexibility, being approximately 57% more flexible than the WaveOne Gold with a 28 mm deflection during bending. Conversely, the V Taper 2H exhibited the highest stress levels in bending tests. While torsional stress was comparable among V Taper 2H, ProGlider, and WaveOne Gold at approximately 500 MPa, R-Pilot showed the highest stress values under torsional loads. Additionally, distinct differences in stress distribution were observed between reciprocating and rotational glide paths. CONCLUSIONS: These insights underscore the necessity of evaluating both bending and torsion behaviors to optimize the design and clinical performance of glide path instruments.