There are various factors affecting the fracture of NiTi rotary files. This study was performed to evaluate the effect of cross sectional area, pecking motion and pecking distance on the cyclic fatigue fracture of different NiTi files. Five different NiTi files-Profile®(Maillefer, Ballaigue, Switzerland), ProTaper™ (Maillefer, Ballaigue, Switzerland), K3® (SybronEndo, Orange, CA), Hero 642® (Micro-mega, Besancon, France), Hero Shaper®(Micro-mega, Besancon, France)-were used. Each file was embedded in temporary resin, sectioned horizontally and observed with scanning electron microscope. The ratio of cross-sectional area to the circumscribed circle was calculated. Special device was fabricated to simulate the cyclic fatigue fracture of NiTi file in the curved canal,. On this device, NiTi files were rotated (300rpm) with different pecking distances (3 mm or 6 mm) and with different motions (static motion or dynamic pecking motion). Time until fracture occurs was measured. The results demonstrated that cross-sectional area didn't have any effect on the time of file fracture. Among the files, Profile® took the longest time to be fractured. Between the pecking motions, dynamic motion took the longer time to be fractured than static motion. There was no significant difference between the pecking distances with dynamic motion, however with static motion, the longer time was taken at 3mm distance. In this study, we could suggest that dynamic pecking motion would lengthen the time for NiTi file to be fractured from cyclic fatigue.
Photograph and schematic diagram of device used in the experiment.
Figure 2
Sliding metal block with having guiding path.
Figure 3
Cross-sectional electronic microscopic photograph of Profile®.
Figure 4
Cross-sectional electronic microscopic photograph of ProTaper™.
Figure 5
Cross-sectional electronic microscopic photograph of K3®.
Figure 6
Cross-sectional electronic microscopic photograph of Hero 642®.
Figure 7
Cross-sectional electronic microscopic photograph of Hero Shaper®.
Table 1
NiTi rotary files used in this experiment
Table 2
Average fracture time and standard deviation(second)
REFERENCES
1. Serene TP, Adams JD, Saxena A. Nickel-Titanium instruments: applications in Endodontics. 1995;St.Louis: Ishiyaku EuroAmerica, Inc.
2. Yoneyama T, Doi H, Hamanaka H. Influence of composition and purity on tensile properties of NiTi alloy castings. Dent Mater J. 1992;11: 157-164.ArticlePubMed
3. Walia HM, Brantley WA, Gerstein H. An initial investigation of the bending and torsional properties of nitinol root canal files. J Endod. 1988;14: 346-351.PubMed
4. Stoekel D, Yu W. Superelastic NiTi wire. Wire J Int. 1991;3: 45-50.
5. Glossen CR, Haller RH, Dove SB, del Rio CE. A comparison of root canal preparations using NiTi hand, NiTi engine driven, and K-Flex endodontic enstruments. J Endod. 1995;21: 146-151.PubMed
6. Cohen S, Burns RC. Pathways of the pulp. 1998;7th ed. St.Louis: Mosby Year Book, Inc; 255.
7. Serene TP, Adams JD, Saxena A. Nickel-Titanium instruments: applications in Endodontics. 1995;St.Louis: Ishiyaku EuroAmerica, Inc; 62-63.
8. Zelada G, Varela P, Martin B, Bahilo JG, Magan F, Ahn S. The effect of rotational speed and the curvature of root canals on the breakage of rotary endodontic instruments. J Endod. 2002;28: 540-542.ArticlePubMed
10. Turpin YL, Chagneau F, Vulcain JM. Impact of two theoretical cross-sections on torsional and bending stresses of nickel-titanium root canal instrument models. J Endod. 2000;26: 414-417.ArticlePubMed
11. Li UM, Lee BS, Shih CT, Lan WH, Lin CP. Cyclic fatigue of endodontic nickel titanium rotary instruments: Static and dynamic tests. J Endod. 2002;28: 448-451.PubMed
12. Shin YM, Kim ES, Kim KM, Kum KY. Effect Of surface defects and cross-sectional configuration on the fatigue fracture of NiTi rotary files under cyclic loading. J Korean Acad Conserv Dent. 2004;29: 267-272.Article
13. Park WK, Lee HJ, Hur B. Sahping ability of NiTi rotary files. J Korean Acad Conserv Dent. 2004;29: 44-50.
14. Lee JH, Kim MJ, Seok CI, Lee WC, Baek SH. Evaluation of canal preparation with NiTi rotary files by micro computed tomography. J Korean Acad Conserv Dent. 2004;29: 378-385.Article
15. Haïkel Y, Sefaty R, Bateman G, Senger B, Allemann C. Dynamic and cyclic fatigue test of engine-driven rotary nicketl titanium endodontic instruments. J Endod. 1999;25: 434-440.PubMed
Tables & Figures
Figure 1
Photograph and schematic diagram of device used in the experiment.
Figure 2
Sliding metal block with having guiding path.
Figure 3
Cross-sectional electronic microscopic photograph of Profile®.
Figure 4
Cross-sectional electronic microscopic photograph of ProTaper™.
Figure 5
Cross-sectional electronic microscopic photograph of K3®.
Figure 6
Cross-sectional electronic microscopic photograph of Hero 642®.
Figure 7
Cross-sectional electronic microscopic photograph of Hero Shaper®.
Table 1
NiTi rotary files used in this experiment
Table 2
Average fracture time and standard deviation(second)
REFERENCES
1. Serene TP, Adams JD, Saxena A. Nickel-Titanium instruments: applications in Endodontics. 1995;St.Louis: Ishiyaku EuroAmerica, Inc.
2. Yoneyama T, Doi H, Hamanaka H. Influence of composition and purity on tensile properties of NiTi alloy castings. Dent Mater J. 1992;11: 157-164.ArticlePubMed
3. Walia HM, Brantley WA, Gerstein H. An initial investigation of the bending and torsional properties of nitinol root canal files. J Endod. 1988;14: 346-351.PubMed
4. Stoekel D, Yu W. Superelastic NiTi wire. Wire J Int. 1991;3: 45-50.
5. Glossen CR, Haller RH, Dove SB, del Rio CE. A comparison of root canal preparations using NiTi hand, NiTi engine driven, and K-Flex endodontic enstruments. J Endod. 1995;21: 146-151.PubMed
6. Cohen S, Burns RC. Pathways of the pulp. 1998;7th ed. St.Louis: Mosby Year Book, Inc; 255.
7. Serene TP, Adams JD, Saxena A. Nickel-Titanium instruments: applications in Endodontics. 1995;St.Louis: Ishiyaku EuroAmerica, Inc; 62-63.
8. Zelada G, Varela P, Martin B, Bahilo JG, Magan F, Ahn S. The effect of rotational speed and the curvature of root canals on the breakage of rotary endodontic instruments. J Endod. 2002;28: 540-542.ArticlePubMed
10. Turpin YL, Chagneau F, Vulcain JM. Impact of two theoretical cross-sections on torsional and bending stresses of nickel-titanium root canal instrument models. J Endod. 2000;26: 414-417.ArticlePubMed
11. Li UM, Lee BS, Shih CT, Lan WH, Lin CP. Cyclic fatigue of endodontic nickel titanium rotary instruments: Static and dynamic tests. J Endod. 2002;28: 448-451.PubMed
12. Shin YM, Kim ES, Kim KM, Kum KY. Effect Of surface defects and cross-sectional configuration on the fatigue fracture of NiTi rotary files under cyclic loading. J Korean Acad Conserv Dent. 2004;29: 267-272.Article
13. Park WK, Lee HJ, Hur B. Sahping ability of NiTi rotary files. J Korean Acad Conserv Dent. 2004;29: 44-50.
14. Lee JH, Kim MJ, Seok CI, Lee WC, Baek SH. Evaluation of canal preparation with NiTi rotary files by micro computed tomography. J Korean Acad Conserv Dent. 2004;29: 378-385.Article
15. Haïkel Y, Sefaty R, Bateman G, Senger B, Allemann C. Dynamic and cyclic fatigue test of engine-driven rotary nicketl titanium endodontic instruments. J Endod. 1999;25: 434-440.PubMed
Citations
Citations to this article as recorded by
Comparative Study Assessing the Canal Cleanliness Using Automated Device and Conventional Syringe Needle for Root Canal Irrigation—An Ex-Vivo Study Keerthika Rajamanickam, Kavalipurapu Venkata Teja, Sindhu Ramesh, Abdulaziz S. AbuMelha, Mazen F. Alkahtany, Khalid H. Almadi, Sarah Ahmed Bahammam, Krishnamachari Janani, Sahil Choudhari, Jerry Jose, Kumar Chandan Srivastava, Deepti Shrivastava, Shankarg Materials.2022; 15(18): 6184. CrossRef
Vibrations Generated by Several Nickel-titanium Endodontic File Systems during Canal Shaping in an Ex Vivo Model Dong-Min Choi, Jin-Woo Kim, Se-Hee Park, Kyung-Mo Cho, Sang Won Kwak, Hyeon-Cheol Kim Journal of Endodontics.2017; 43(7): 1197. CrossRef
Effect of cross-sectional area of 6 nickel-titanium rotary instruments on the fatigue fracture under cyclic flexural stress: A fractographic analysis Soo-Youn Hwang, So-Ram Oh, Yoon Lee, Sang-Min Lim, Kee-Yeon Kum Journal of Korean Academy of Conservative Dentistry.2009; 34(5): 424. CrossRef