A comparative study of glide path instruments assessing flexibility and torsion by finite element method

Area of Science:

• Endodontics
• Materials Science
• Biomechanical Engineering

Background:

• Nickel-titanium (NiTi) glide path instruments are crucial in endodontic procedures.
• Understanding their mechanical behavior under clinical stress is essential for preventing instrument failure.
• This study addresses a gap by numerically evaluating bending and torsion of four NiTi glide path instruments.

Purpose of the Study:

• To numerically evaluate the bending and torsion behavior of four different NiTi glide path instruments.
• To compare their mechanical performance under simulated clinical conditions.
• To identify design characteristics influencing instrument flexibility and stress distribution.

Main Methods:

• Four NiTi glide path instruments (WaveOne Gold Glider, R-Pilot, ProGlider, V Taper 2H) were modeled using CAD software.
• Finite element analysis (FEA) was performed in SolidWorks.
• Material properties and boundary conditions adhered to ISO 3630-1 standards for bending and torsion tests.

Main Results:

• Significant variations in stress distribution and flexibility were observed among the instruments.
• R-Pilot exhibited superior flexibility (57% more than WaveOne Gold) but higher torsional stress.
• V Taper 2H showed the highest bending stress; torsional stress was comparable for V Taper 2H, ProGlider, and WaveOne Gold.

Conclusions:

• Both bending and torsion behaviors must be evaluated for comprehensive assessment of NiTi glide path instruments.
• Instrument design, including cross-sectional shape, significantly impacts mechanical performance.
• These findings can inform the optimization of NiTi glide path instruments for improved clinical outcomes.