A comparative finite analysis of the mechanical behavior of ProTaper NEXT and WaveOne rotary files

• Published in: Bulletin of the National Research Centre 2019-10, Vol.43 (1), p.1-6, Article 148
• Main Authors: Omar, Nada, Ismail, Amira Galal, Galal, Manar, Zaazou, Mohamed H., Mohamed, Mohamed Abdullah
• Format: Article
• Language: English
• Subjects: Accumulation; Bending; CAD; Computer aided design; Computer programs; Computer simulation; Concentrated loads; Displacement; Evaluation; Finite element analysis; Finite element method; Humanities and Social Sciences; Load distribution; Mathematical analysis; Mathematical models; Mechanical properties; multidisciplinary; Nickel; NiTi rotary files; ProTaper NEXT; Residual stress; Science; Science (multidisciplinary); Software; Software packages; Stress concentration; Stress distribution; Technology; Three dimensional analysis; Three dimensional models; Titanium; Torque; Torsion stresses; Torsional stress; Two dimensional models; WaveOne; Wire
• ISSN: 2522-8307; 2522-8307
• DOI: 10.1186/s42269-019-0183-x

Finite element analysis was used to evaluate the stress distribution, estimate the residual stresses, bending, and amount of displacement of two nickel-titanium instruments manufactured by the same M-wire technology but with different cross-section. Materials and methods Two brands of Ni-Ti instruments ProTaper NEXT (Dentsply Maillefer), and WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) were scanned with stereomicroscope to produce a two-dimensional model for each file using computer-aided design programs (CAD) (SolidWorks software package), which then was converted into stereolithographic extension to be readable by programming software (MATLAB software) to produce three-dimensional models. The mathematical analysis of files was performed on SolidWorks software package. The mechanical behavior of the two files was analyzed numerically in a SolidWorks package to simulate and measure torsion, bending, and file displacement. Application of a shear moment (torsion) 2.5 N/mm moment of force was applied to the shaft in a clockwise direction, while the last 4 mm of the tip was rigidly constrained to evaluate the stress distribution on each file. As for Cantilever bending, a concentrated load of 1 N at the tip of the file with its shaft rigidly held in place was applied for the finite element models. The vertical displacement was measured and the von Mises stress distribution was evaluated. Results The WaveOne file showed higher torsional stresses accumulation than those accumulated in the ProTaper NEXT. While the ProTaper NEXT showed more bending and file displacement than those showed by WaveOne file. Conclusions The two files rotary models highlighted the different mechanical properties of the files although they share the same manufactured technology M-wire. The ProTaper NEXT showed less torsional stress accumulation and more bending properties.