In vitro evaluation of cyclic fatigue resistance of thermally treated novel nickel-titanium rotary instruments




Dental Instruments; Endodontics; Rotação.


The objective of this study was to evaluate the cyclic fatigue resistance of novel NiTi files (subjected to heat treatment) using the in vitro model (artificial canal). Twelve ProDesign Logic instruments - PDL 25/.06 (Easy Equipamentos Odontológicos, Belo Horizonte, Brazil) and 12 Protaper Next X2 instruments - PTN (tip 25) were included in this research. The Static cyclic fatigue test was performed with a grooved stainless steel block simulating a canal of 1,5 mm diameters, a 60o angle of curvature and 5 mm radius. The files were positioned inside the artificial canal and rotated until the fracture occurred. Using the time until fracture (seconds) and the number of rotations per minute (RPM), the number of cycles until fracture (NCF) was calculated and the length of ruptured fragments was registered. Three samples from each group were analyzed in Scanning Electronic Microscopy (SEM) to characterize the metal rupture. Data were analyzed using the Mann-Whitney non-parametric test and the level of significance considered was p<0.05. PDL obtained a mean value of 956,0 NCF (352,0 - SD) and PTN achieved 391,0 NCF (36.7 - SD) with statistical significance between the groups (p < 0.001). There was no statistical difference on fragment length (p > 0.05). SEM analysis showed features compatible with ductile fracture. ProDesign LOGIC files showed higher NCF than Protaper Next X2. There was no difference between groups considering the length of the ruptured fragment.


Alcalde, M. P., Tanomaru-Filho, M., Bramante, C. M., Duarte, M. A. H., Guerreiro-Tanomaru, J. M., Camilo-Pinto, J., Só, M. V. R. & Vivan, R. R. (2017). Cyclic and Torsional Fatigue Resistance of Reciprocating Single Files Manufactured by Different Nickel-titanium Alloys. J Endod , 43(7):1186-91.

Bhagabati, N., Yadav, S. & Talwar, S. (2012). An in vitro cyclic fatigue analysis of different endodontic nickel-titanium totary instruments. J Endod, 38(4):515- 8.

Capar, I. D., Ertas, H. & Arslan, H. (2015). Comparison of cyclic fatigue resistance of novel nickel-titanium rotary instruments. Aust Endod J, 41:24-8.

Capar, I. D., Kaval, M.E., Ertas, H. & Sen BH. (2015). Comparison of the cyclic fatigue resistance of 5 different rotary pathfinding instruments made of conventional nickel-titanium wire, M-wire, and controlled memory wire. J Endod, 41(4):535-8.

Cheung, G., Zhang, E., Zheng, Y., et al. (2011). A numerical method for predicting the bending fatigue life of niti and stainless steel root canal instruments. Int Endod J, 44(4):357-1.

De-Deus, G., Moreira, E., Lopes, H., et al. (2010). Extended cyclic fatigue life of F2 protaper instruments used in reciprocating movement. Int Endod J, 43(12):1063-8.

de Menezes, S. E. A. C., Batista, S. M., Lira, J. O. P. & de Melo Monteiro G. Q. (2017). Cyclic Fatigue Resistance of WaveOne Gold, ProDesign R and ProDesign Logic Files in Curved Canals In Vitro. Iran Endod, 12(4):468-3.

Gündoğar, M. & Özyürek, T. (2017). Cyclic Fatigue Resistance of OneShape, HyFlex EDM, WaveOne Gold, and Reciproc Blue Nickel-titanium Instruments. J Endod, 43(7):1192-6.

Haïkel, Y., Serfaty, R., Bateman, G., et al. (1999). Dynamic and cyclic fatigue of engine-driven rotary nickel-titanium endodontic instruments. J Endod, 25(6):434-40.

Hua, P., Xia, M., Onuki, Y. & Sun, G. (2021) Nanocomposite NiTi shape memory alloy with high strength and fatigue resistance. Nat Nanotechnol. 16(4):409-13.

Kim, T., Cheung, G., Lee, M., et al. (2009). Stress distribution of three niti rotary files under bending and torsional conditions using mathematic analysis. Int Endod J, 42(1):14-21.

Kitchens, G., Liewehr, F. & Moon P. (2007). The effect of operational speed on the fracture of nickel-titanium rotary instruments. J Endod, 33(1):52-4.

Kuhn, G. & Jordan, L. (2002). Fatigue and mechanical properties of nickel-titanium endodontic instruments. J Endod, 28(10):716-20.

Kwak, S. W., Lee, J. Y., Goo, H. J. & Kim HC. (2017). Effect of surface treatment on the mechanical properties of nickel-titanium files with a similar cross-section. Restor Dent Endod, 42(3):216-23.

Lee, M. H., Versluis, A., Kim, B. M., et al. (2011). Correlation between experimental cyclic fatigue resistance and numerical stress analysis for nickel-titanium rotary files. J Endod, 37(8):1152-7.

Özyürek, T., Gündoğar, M., Yılmaz, K. & Uslu G. (2017). Bending resistance and cyclic fatigue life of Reciproc Blue, WaveOne Gold, and Genius files in a double (S-shaped) curved canal. J Dent Res Dent Clin Dent Prospects, 11(4):241-6.

Pereira, E. S., Peixoto, I. F., Viana, A. C., Oliveira, I. I., Gonzalez, B. M., Buono, V. T. & Bahia M. G. (2012). Physical and mechanical properties of a thermomechanically treated NiTi wire used in the manufacture of rotary endodontic instruments. Int Endod J, 45(5):469-74.

Pirani, C., Cirulli, P., Chersoni, S., et al. (2011). Cyclic fatigue testing and metallographic analysis of nickel-titanium rotary instruments. J Endod, 37(7):1013-6.

Ruiz-Sánchez, C., Faus-Llácer, V., Faus-Matoses, I., Zubizarreta-Macho, Á., Sauro, S. & Faus-Matoses, V. (2020). The Influence of NiTi Alloy on the Cyclic Fatigue Resistance of Endodontic Files. J Clin Med, 21(11):3755.

Sattapan, B., Nervo, G. J., Palamara, J. E. et al (2000). Defects in rotary nickel-titanium files after clinical use. J Endod, 26(3):161-5.

Shen, Y., Cheung, G., Peng, B., et al. (2009). Defects in nickel-titanium instruments after clinical use. Part 2: fractographic analysis of fractures surface in a cohort study. J Endod, 35(1):133-6.

Shen, Y., Haapasalo, M., Cheung, G., et al. (2009). Defects in nickel-titanium instruments after clinical use. Part 1: relationship between observed imperfections and factors leading to such defects in a cohort study. J Endod, 35(1):129-32.

Shen, Y., Qian, W., Abtin, H., Gao, Y. & Haapasalo M. (2011). Fatigue testing of controlled memory wire nickel-titanium rotary instruments. J Endod, 37(7):997-1001.

Shen, Y., Zhou, H., Zheng, Y., et al. (2011). Metallurgical characterization of controlled memory wire nickel-titanium rotary instruments. J Endod, 37(11):1566-71.

Silva, E. J., Rodrigues, C., Vieira, V. T., Belladonna, F. G., De-Deus, G. & Lopes, H. P. (2016).Bending resistance and cyclic fatigue of a new heat-treated reciprocating instrument. Scanning, 38(6):837-41.

Uygun, A. D., Kol, E., Topcu, M. K., Seckin, F., Ersoy, I. & Tanriver M. (2016). Variations in cyclic fatigue resistance among ProTaper Gold, ProTaper Next and ProTaper Universal instruments at different levels. Int Endod J, 49(5):494-9.

Viana, A., Craveiro, M., Bahia, M., et al. (2010). Relationship between flexibility and physical, chemical and geometrical characteristics of rotary nickel-titanium instruments. Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 110(4):527-33.

Wealleans, J., Kirkpatrick, T., Rutledge, R., et al. (2011). The effects of dentin debris on the cyclic fatigue resistance of several nickel titanium rotary systems. Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 112(3):390-5.




How to Cite

ASSAF, B. R. .; VERÇOSA, J. C.; COSTA, V. H. da S. .; SANTOS , A. M. C. .; FROZONI , M. .; FERNANDES , A. M. . In vitro evaluation of cyclic fatigue resistance of thermally treated novel nickel-titanium rotary instruments . Research, Society and Development, [S. l.], v. 11, n. 7, p. e32211729870, 2022. DOI: 10.33448/rsd-v11i7.29870. Disponível em: Acesso em: 6 jul. 2022.



Health Sciences