Evaluation of the Cyclic Fatigue and Torsional Resistance of Novel Nickel-Titanium Rotary Files with Various Alloy Properties

Protaper Universal (PTU), Protaper Gold (PTG) (Maillefer, Ballaigues, CH), EdgeTaper (ET), and EdgeTaper Platinum (ETP) (Albuquerque, NM, USA) were tested for both torsional and flexural resistance. The aim of the present study was to evaluate the influence of proprietary heat treatment on the metallurgical properties of the aforementioned instruments. Four groups of 30 different instruments (size 20.07) were tested, then divided into two subgroups of 15 instruments—one for the cyclic fatigue test in a curved canal (90°—2 mm radius) at 300 rpm and 2.5 Ncm. The time to fracture (TtF) and fragment length (FL) were recorded. The other subgroup was subjected to the torsional test (300 rpm, 5.5 Ncm). The torque to fracture and TtF were recorded. All the instruments underwent a SEM analysis. The heat-treated instruments showed a significantly higher fatigue resistance than the non-heat-treated instruments (p < 0.05). No significant differences were found in the torsional resistance between the ET and PTU, and the ETP and PTG. However, when comparing all the groups, the heat-treated instruments showed less torsional resistance. The improvement from heat treatment was mainly found in the cyclic fatigue resistance.

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Effect of Electropolishing ProFile Nickel–Titanium Rotary Instruments on Cyclic Fatigue Resistance, Torsional Resistance, and Cutting Efficiency

Journal of Endodontics ◽

10.1016/j.joen.2007.10.007 ◽

2008 ◽

Vol 34 (2) ◽

pp. 190-193 ◽

Cited By ~ 52

Author(s):

Tung B. Bui ◽

John C. Mitchell ◽

J. Craig Baumgartner

Keyword(s):

Fatigue Resistance ◽

Cyclic Fatigue ◽

Nickel Titanium ◽

Cutting Efficiency ◽

Torsional Resistance ◽

Rotary Instruments

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Evaluation of the effect of temperature on cyclic fatigue resistance of three types of Nickel-Titanium rotary files with various alloy properties: An in vitro study

Erbil Dental Journal ◽

10.15218/edj.2019.05 ◽

2019 ◽

Vol 2 (1) ◽

pp. 157-163

Author(s):

Dara Saeed ◽

Fadi Rafea

Keyword(s):

Fatigue Resistance ◽

In Vitro Study ◽

Cyclic Fatigue ◽

Nickel Titanium ◽

Vitro Study ◽

Effect Of Temperature ◽

Alloy Properties

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Evaluation of the Flexibility, Cyclic Fatigue, and Torsional Resistance of Rotary Endodontic Files Made of Different Nickel-Titanium Alloys

International Journal of Dentistry and Oral Science ◽

10.19070/2377-8075-si08001 ◽

2016 ◽

pp. 1-5

Author(s):

Lopes HP ◽

◽

Lopes WSP ◽

Vieira VTL ◽

Elias CN ◽

...

Keyword(s):

Titanium Alloys ◽

Cyclic Fatigue ◽

Nickel Titanium ◽

Torsional Resistance ◽

Nickel Titanium Alloys

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Effect of synchronous irrigation on cyclic fatigue of nickel-titanium instrument in the dynamic and static models

Journal of Applied Biomaterials & Functional Materials ◽

10.1177/2280800020987403 ◽

2021 ◽

Vol 19 ◽

pp. 228080002098740

Author(s):

Haiyun Liu ◽

Yanfeng Li ◽

Guangquan Chai ◽

Yuan Lv ◽

Changjian Li ◽

...

Keyword(s):

Fatigue Resistance ◽

Flow Rate ◽

Dynamic Control ◽

Cyclic Fatigue ◽

Nickel Titanium ◽

Control Group ◽

Time To Failure ◽

Dynamic Tests ◽

Significant Difference ◽

Experimental Group

Objective: To evaluate the effect of synchronous water irrigation on the fatigue resistance of nickel-titanium instrument. Methods: A standardized cyclic fatigue test models were established, and five types of nickel-titanium instruments (PTU F1, WO, WOG, RE, and M3) were applied. Each instrument was randomly divided into two groups ( N = 12). There was synchronous water irrigation in the experimental group, and no water irrigation in the control group. Besides, ProTaper Universal F1 was randomly divided into 10 groups ( N = 20). In the static group, nickel-titanium instruments were divided into one control group (no irrigation, N = 20) and six experimental group (irrigation, N = 20) based on different flow rate, angle and position; while in the dynamic group, instruments were divided into one control group (no irrigation, N = 20) and two experimental group (irrigation, N = 20) based on different flow rate. The rotation time (Time to Failure, TtF) of instruments was recorded and analyzed. Results: According to the static experiments, the TtF of instruments in all experimental groups was significantly higher than that in the static control group. Besides, the dynamic tests of PTU F1 showed that the TtF in the experimental group was significantly higher than that in the dynamic control group. Compared with control group, the TtF in the experimental groups increased by at least about 30% and up to 160%. The static and dynamic tests of PTU F1 showed that the TtF of nickel-titanium instrument in all experimental groups was significantly higher than that in the control group. However, there was no significant difference between any two experimental groups. Conclusion: Regardless of dynamic or static model, TtF with irrigation was longer than that with non-irrigation, indicating that synchronous irrigation can increase the fatigue resistance of nickel-titanium instrument. However, different irrigation conditions may have the same effect on the fatigue resistance.

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Finite element analysis comparing WaveOne Gold and ProTaper Next endodontic file segments subjected to bending and torsional load

Bulletin of the National Research Centre ◽

10.1186/s42269-019-0215-6 ◽

2019 ◽

Vol 43 (1) ◽

Author(s):

Amira Galal Ismail ◽

Mohamed Hussein Abdelfattah Zaazou ◽

Manar Galal ◽

Nada Omar Mostafa Kamel ◽

Mohamed Abdulla Nassar

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Three Dimensional ◽

Clinical Situation ◽

Nickel Titanium ◽

Behavioral Differences ◽

Element Analysis ◽

Torsional Resistance ◽

Computer Tomography Scanning ◽

Cantilever Bending

Abstract Background The objective of this study was to assess the bending and torsional properties of two nickel-titanium endodontic files with equivalent sizes and various designs and alloys using finite element analysis, ProTaper Next®X2 (PTN) size 25 with 0.06 taper and WaveOne Gold® (WOG) primary size 25 with 0.07 taper. Methodology Two-dimensional models of the two files PTN and WOG were created using computer tomography scanning and stereomicroscope to produce a three-dimensional digital model. Instrument behavior under bending or torsional conditions was numerically analyzed in SolidWorks software package. Result ProTaper Next® revealed higher flexibility than WaveOne Gold® when exposed to cantilever bending but showed higher stress accumulation than WOG. In terms of torsional resistance, PTN also revealed higher torsional resistance than WOG. Conclusion The geometry of the instrument, thermomechanical treatment of the alloy, and its composition affect the mechanical behavior (bending and torsion) of nickel titanium rotary files. Hence, being aware of these behavioral differences, each clinician will be able to use the adequate file according to the clinical situation in addition to the manufacturer’s instructions.

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