Assessment of the role of cross section on fatigue resistance of rotary files when used in reciprocation

ABSTRACT Objective: The purpose of this study was to assess the role of cross section on cyclic fatigue resistance of One Shape, Revo-S SU, and Mtwo rotary files in continuous rotation and reciprocating motion in dynamic testing model. Materials and Methods: A total of 90 new rotary One Shape, Revo-S SU, and Mtwo files (ISO size 25, taper 0.06, length 25 mm) were subjected to continuous rotation or reciprocating motion. A cyclic fatigue testing device was fabricated with 60° angle of curvature and 5 mm radius. The dynamic testing of these files was performed using an electric motor which permitted the reproduction of pecking motion. All instruments were rotated or reciprocated until fracture occurred. The time taken for each instrument to fracture was recorded. All the fractured files were analyzed under a scanning electron microscope (SEM) to detect the mode of fracture. Statistical analysis was performed using one-way ANOVA, followed by Tukey's honestly significant difference post hoc test. Results: The time taken for instruments in reciprocating motion to fail under cyclic loading was significantly longer when compared with groups in continuous rotary motion. There was a statistically significant difference between Mtwo rotary and the other two groups in both continuous and reciprocating motion. One Shape rotary files recorded significantly longer duration to fracture resistance when compared with Revo-S SU files in both continuous and reciprocating motion. SEM observations showed that the instruments of all groups had undergone a ductile mode of fracture. Conclusion: Reciprocating motion improved the cyclic fatigue resistance of all tested groups.

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Assessment of cyclic fatigue resistance of Protaper Next and WaveOne Gold in different kinematics

Bulletin of the National Research Centre ◽

10.1186/s42269-020-00421-w ◽

2020 ◽

Vol 44 (1) ◽

Author(s):

Amira Galal Ismail ◽

Manar Galal ◽

Nehal Nabil Roshdy

Keyword(s):

Fatigue Resistance ◽

Fatigue Testing ◽

Cyclic Fatigue ◽

Rotation Group ◽

Radius Of Curvature ◽

Testing Device ◽

Reciprocating Motion ◽

Continuous Rotation ◽

Custom Made ◽

Rotation Motion

Abstract Background The purpose of the current study was to inspect and compare the influence of applying continuous rotation and reciprocation motions on the cyclic fatigue resistance of Protaper Next (PTN) file (X2) and WaveOne Gold (WOG) Primary file in simulated canals. Twenty Protaper Next files(X2) and 20 WaveOne Gold Primary files were included in this study. A cyclic fatigue testing device was employed to test the cyclic resistance of each file in different motions. The testing device has an artificial custom-made stainless-steel canal with a 60° angle of curvature and a 2-mm radius of curvature. The files were randomly divided into 4 groups; group 1: PTN in continuous rotation, group 2: PTN in reciprocation, group 3: WOG in continuous rotation and group 4: WOG in reciprocation. All the instruments were rotated until fracture occurred, and the time to fracture was recorded in seconds using a digital chronometer. The number of cycles to fracture (NCF) was calculated. The data were analyzed statistically (p < .05). Results Results represented that when using either continuous rotation motion or reciprocating motion, WOG files showed a significantly longer time until failure than PTN files (p < 0.001). The time till fracture increased significantly, when using both types of files with a reciprocating filing motion. Conclusion Within the confinement of this study, WOG file in reciprocation showed higher cyclic fatigue resistance than PTN in both continuous rotation and reciprocating motion. The reciprocating motion enhances both files behavior in terms of cyclic fatigue resistance.

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Comparison of Apical Transportation, Centering Ability and Cyclic Fatigue Resistance of Four Rotary File Systems

Dental Journal of Advance Studies ◽

10.1055/s-0038-1672008 ◽

2015 ◽

Vol 03 (01) ◽

pp. 012-019

Author(s):

Ankita Sood ◽

Varun Jindal ◽

Ajay Chhabra ◽

Arvind Arora ◽

Ankur Vats

Keyword(s):

Fatigue Resistance ◽

Fatigue Testing ◽

File Systems ◽

Cyclic Fatigue ◽

Root Canal Preparation ◽

Maxillary Molars ◽

Apical Transportation ◽

Significant Difference ◽

Before And After ◽

Canal Transportation

Abstract Aim: The aim of this study was to evaluate the apical transportation, centering ability and cyclic fatigue resistance of Hero shaper, Twisted file, Hyflex file and RACE rotary file systems. Methods: Mesiobuccal roots of eighty maxillary molars were divided into four groups and instrumented with Hero shaper, Twisted file, Hyflex file and RACE rotary file systems with a final apical size being 25/.04. Apical deviation was assessed by the radiographic platform method that enables obtaining superimposed images of the first and last instrument used in root canal preparation in the same radiograph. Apical transportation was measured in millimeters with the aid of the AUTOCAD 2008 software. Forty canals were sectioned at 7mm from the apex and stereomicroscopic Images were taken at 6x magnification before and after instrumentation for evaluation of centering ability. The cyclic fatigue testing was conducted with the instrumentrotating freely at angles of curvature of 45 degree. Total 10 instruments were tested in each group. The instruments were rotated at 400rpm using the X-smart motor (Dentsply, Maillefer) until fracture occurred. Results: There was no statistically significant difference between the four groups in apical transportation and centering ability whereas twisted files showed the maximum cyclic fatigue resistance. Conclusion: The different rotary file systems provided minimum canal transportation and the twisted file performed significantly better in terms of cyclic fatigue resistance.

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Comparison of Cyclic Fatigue Resistance of Heat-Treated Nickel-Titanium Reciprocating Instruments at the Intracanal Temperature

Balkan Journal of Dental Medicine ◽

10.2478/bjdm-2021-0014 ◽

2021 ◽

Vol 25 (2) ◽

pp. 87-91

Author(s):

Neslihan Büşra Keskin ◽

Gürkan Güneç

Keyword(s):

Fatigue Resistance ◽

Cyclic Fatigue ◽

Radius Of Curvature ◽

Heat Treated ◽

Significant Difference ◽

Number Of Cycles ◽

The Moment ◽

The One ◽

Post Hoc ◽

Different Characteristics

Summary Background/Aim: The aim of the present study was to compare the cyclic fatigue resistance of NiTi files running with reciprocal motion and having different characteristics (RPC Blue, WOG, EndoArt Wise Reciproc Gold, EndoArt Wise Reciproc Blue) at the intracanal temperature (35°C) by using NaOCl irrigation solution. Material and Methods: Totally 60 WaveOne GOLD (Dentsply-Sirona, Ballaigues, Switzerland), Reciproc Blue (VDW, Munich, Germany), EndoArt Wise Reciproc Gold, and EndoArt Wise Blue (Inci Dental Productions Co, Istanbul, Turkey) (n= 15) files were used. Each of the rotary files were tested at the intracanal temperature (35°C) using a dynamic model in a stainless-steel artificial canal with an inner diameter of 1.5 mm, 60° angle of curvature, and 2mm radius of curvature until fracture occurred. The device automatically stopped at the moment of fracture and the number of cycles to the fracture was calculated as per second. The lengths of fractured parts were measured using a digital microcaliper. The One-Way Analysis of Variance (ANOVA) and Tukey’s post-hoc tests were used for intergroup comparisons. Results: In 2 mm Radius of curvature, the EndoArt Wise Reciproc Blue group had a significantly higher time to fracture followed by the EndoArt Wise Reciproc Gold, Resiproc Blue, WaveOne Gold. No significant difference was found between EndoArt Wise Reciproc Gold and Resiproc Blue groups (P>0.05). Among the groups, there was no statistically significant difference in the lengths of fractured parts of the instruments (P> 0.05). Conclusions: EndoArt Wise Reciproc Blue files exhibited significantly higher cyclic fatigue resistance compared with other files tested in a 2-mm radius of curvature and a 60° angle in an artificial canal at the intracanal temperature.

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Evaluation of Cyclic Fatigue of Hyflex EDM, Twisted Files, and ProTaper Gold Manufactured with Different Processes: An In Vitro Study

International Journal of Dentistry ◽

10.1155/2021/7402658 ◽

2021 ◽

Vol 2021 ◽

pp. 1-6

Author(s):

Pooja D. Khandagale ◽

Prashant P. Shetty ◽

Saleem D. Makandar ◽

Pradeep A. Bapna ◽

Mohmed Isaqali Karobari ◽

...

Keyword(s):

Fatigue Resistance ◽

Root Canal ◽

File Systems ◽

In Vitro Study ◽

Cyclic Fatigue ◽

Segment Length ◽

Significant Difference ◽

Number Of Cycles ◽

Post Hoc

Introduction. The main aims of root canal instrumentation are to provide an environment that will lead to healing and to provide a root canal shape that is comfortable to clean and seal. When working with rotary endodontic instruments, the most significant concerns are that the instrument might fracture in the root canal, thus affecting the treatment outcome. Hence, it is of immense importance to know which file systems have more cyclic fatigue resistance. Methodology. This study evaluated the effect of the curved segment length of the artificial canal (the arch), and the number of cycles necessary in fracture of Hyflex EDM, Twisted files, and ProTaper Gold were recorded. Sixty NiTi rotary instruments of 25 mm length (Hyflex EDM (20), Twisted files (20), and ProTaper Gold (20)) were tested in a metal block with simulated canal having 90° angle of curvature. The study was performed with a specific radius and degree of curvature, i.e., 8 mm radius and 90⁰ angle of curvature, and data obtained were subsequently subjected to statistical evaluation using one-way analysis of variance and Tukey’s post hoc test. Result. The Hyflex EDM (774.29) exhibited the maximum cyclic fatigue resistance compared to Twisted files (654.875) and ProTaper Gold (375.575). A statistically significant difference was observed between the tested groups. Conclusion. The Hyflex EDM files showed the highest cyclic fatigue resistance, followed by Twisted files and ProTaper Gold files.

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Cyclic Fatigue Resistance of K3, K3XF, and Twisted File Nickel-Titanium Files under Continuous Rotation or Reciprocating Motion

Journal of Endodontics ◽

10.1016/j.joen.2013.07.020 ◽

2013 ◽

Vol 39 (12) ◽

pp. 1585-1588 ◽

Cited By ~ 47

Author(s):

Juan José Pérez-Higueras ◽

Ana Arias ◽

José C. de la Macorra

Keyword(s):

Fatigue Resistance ◽

Cyclic Fatigue ◽

Nickel Titanium ◽

Reciprocating Motion ◽

Continuous Rotation

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Cyclic Fatigue Comparison of TruNatomy, Twisted File, and ProTaper Next Rotary Systems

International Journal of Dentistry ◽

10.1155/2020/3190938 ◽

2020 ◽

Vol 2020 ◽

pp. 1-4

Author(s):

Abdullah Mahmoud Riyahi ◽

Amr Bashiri ◽

Khalid Alshahrani ◽

Saad Alshahrani ◽

Hadi M. Alamri ◽

...

Keyword(s):

Standard Deviation ◽

Fatigue Resistance ◽

Fatigue Testing ◽

Clinical Performance ◽

Cyclic Fatigue ◽

Tooth Structure ◽

Multiple Comparison Test ◽

Continuous Rotation ◽

Number Of Cycles ◽

Cycles To Failure

TruNatomy (TN; Dentsply Sirona, Maillefer, Ballaigues, Switzerland) is a newly released system that was not tested in any previous studies. The objective of this work is to evaluate cyclic fatigue resistance of the new file and compare it with the Twisted Files (TF) and ProTaper Next (PTN). Forty-five files were distributed into 3 groups: PTN X2 (size 25 and taper 0.06), TF (size 25 and taper 0.06), and TN prime file (size 26 and taper 0.04). Each group included 15 files. Lengths of all files were 25 mm. Cyclic fatigue testing was done using artificial stainless-steel canals with 60-degree curvature and 5 mm radius. Continuous rotation movement at 300 rpm was used until the file fractures. Time for file separation was recorded in seconds. The number of cycles to failure (NCF) mean and standard deviation for each group was calculated. For statistical analysis of data, ANOVA and Tukey’s multiple comparison test were used. Mean and standard deviation (SD) of NCF were 259 ± 37.2, 521.67 ± 63.07 and 846.67 ± 37.16 for PTN, TF, and TN respectively. TN on average had significantly the highest NCF compared with PTN (p<0.05) and TF (p<0.05). TruNatomy file showed superior cyclic fatigue resistance. With its potential to preserve tooth structure, this file offers a good cyclic fatigue advantage. However, future studies are required to evaluate other properties of this file and to examine its clinical performance.

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Comparison of Cyclic Fatigue Resistance of Five Heat Treated NiTi Rotary Systems in Single and Double Curved Canals.

10.21203/rs.3.rs-600840/v1 ◽

2021 ◽

Author(s):

Mohammad Al-Obaida ◽

Khalid Merdad ◽

Ali Alkhamis ◽

Muneer Khan Mohammed ◽

Rahaf Al-Obaida ◽

...

Keyword(s):

Fatigue Resistance ◽

Fatigue Testing ◽

Cyclic Fatigue ◽

Radius Of Curvature ◽

Double Curvature ◽

Heat Treated ◽

Separation Pattern ◽

Vortex Blue ◽

Number Of Cycles ◽

Post Hoc

Abstract BackgroundThe aim of this study was to compare cyclic fatigue resistance (CFR) and separation patterns during rotating movement of five heat-treated nickel titanium files in both single and double-curved canals. MethodsCFR was compared between five groups of 24 files each: HyFlex® EDM, HyFlex™ CM, Vortex Blue®, Protaper Next®, and One Curve, by determining the time needed to fracture (TTF) and the number of cycles to failure (NCF) in a cyclic fatigue testing device with a single 5-mm radius of curvature (ROC) and 60° angle, and a double curvature; coronal curvature (5 mm ROC and 60° angle) and apical curvature (2 mm ROC and 70° angle). The separation pattern was evaluated, and file fragment separated length were measured. One-way ANOVA and Tukey’s post-hoc were used to compare statistical differences between the groups. Scanning Electron Microscope (SEM) was used to investigate the fracture sites. Results HyFlex™ CM files displayed significantly higher CFR, followed by HyFlex® EDM and Vortex Blue® in single curvature canals, and Protaper Next® (PTN) in the double curvature canals, as observed by TFF and NCF. PTN group had the highest tendency for files to extrude apically after separation in both curvatures. ConclusionHyFlex™ CM instruments have superior resistance to cyclic flexural fatigue within single canals with single and double curvatures, followed by HyFlex® EDM and Vortex Blue® instruments. Protaper Next® files followed by One Curve had the highest tendency to extrude apically after separationClinical relevanceHyFlex™ CM instruments showed the highest safety in preparing canals with single or double curvatures, considering CFR.

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Evaluation of cyclic fatigue resistance of modern Nickel-Titanium rotary instruments with continuous rotation

Giornale Italiano di Endodonzia ◽

10.4081/j.gien.2017.23 ◽

2017 ◽

Vol 31 (2) ◽

pp. 78-82

Author(s):

Massimo Amato ◽

Giuseppe Pantaleo ◽

Dina Abdellatif ◽

Andrea Blasi ◽

Roberto Lo Giudice ◽

...

Keyword(s):

Statistical Analysis ◽

Fatigue Resistance ◽

Fracture Resistance ◽

Fatigue Testing ◽

Cyclic Fatigue ◽

Nickel Titanium ◽

Whitney Test ◽

Ti Alloys ◽

Rotary Instruments ◽

Continuous Rotation

Aim: The aim of present study was to compare cyclic fatigue resistance of three modern Ni-Ti instruments used with continuous rotation. Materials and methods: For this study 3 groups of rotating instruments with continuous rotation (HyFlex EDM, Twisted File Adaptive, Revo S SU) have been used, each group consisted of 20 files. The various groups were subjected to cyclic fatigue testing through an artificial metal device. A statistical analysis with Kruskal-Wallis test and Mann-Whitney test was performed. Results: There were statistically significant differences between the three groups. The HyFlex EDM instruments have a fracture resistance slightly higher than the Twisted file and far higher than Revo S SU. Conclusions: Modern Ni-Ti alloys increase resistance of the rotating instruments to cyclic fatigue.

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Cyclic fatigue resistance of VDW.ROTATE and Reciproc Blue nickel-titanium files at root canal temperature

Journal of Dental Research Dental Clinics Dental Prospects ◽

10.34172/joddd.2020.032 ◽

2020 ◽

Vol 14 (3) ◽

pp. 177-180

Author(s):

Ahmet Demirhan Uygun

Keyword(s):

Fatigue Resistance ◽

Root Canal ◽

Cyclic Fatigue ◽

Nickel Titanium ◽

Reciprocating Motion ◽

Motion Group ◽

Continuous Rotation ◽

Time To Fracture ◽

Motion Groups ◽

Rotation Motion

Background. This study aimed to compare the VDW.ROTATE instruments with the Reciproc Blue instruments in different kinematics in terms of the cyclic fatigue resistance. Methods. Sixty instruments, 40 VDW.ROTATE and 20 Reciproc Blue instruments, were divided into three groups (n=20): VDW.ROTATE was used in both continuous rotation and reciprocation, and Reciproc Blue was used in reciprocation only. The cyclic fatigue resistance test was carried out in an artificial canal (60°, r=3 mm) at an intracanal temperature of 35±2°C until fracture, and the time to fracture was recorded in seconds. The data were analyzed statistically using Kruskal–Wallis and Tamhane’s T2 tests (P<0.05). Results. DAll the reciprocating motion groups resulted in a longer mean duration to failure than the continuous rotation motion group (P<0.05). Conclusion. It was observed that the Reciproc Blue instruments had higher cyclic fatigue resistance than VDW.ROTATE instruments (P<0.05). Recent studies have shown that reciprocal movement increases cyclic fatigue resistance compared to rotational movement. The VDW.ROTATE instrument, which has a similar size, design, and alloy as the Reciproc Blue instrument, can also be used by clinicians in reciprocating motion with endo motors capable of reciprocating in different directions. However, even if the cyclic fatigue resistance increases by using VDW.ROTATE instruments in reciprocation, the cyclic fatigue resistance is lower than Reciproc Blue instruments.

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