scholarly journals Influence of cross-section and number of use in cyclic fatigue resistance of rotary instruments

2019 ◽  
Vol 18 ◽  
pp. e191208
Author(s):  
Luís César Brisighello ◽  
George Táccio de Miranda Candeiro ◽  
Luiza Riomar Paz ◽  
Hermano Camelo Paiva ◽  
Giulio Gavini

Aim: The aim of present study was to evaluate if the cross-section and the number of use have influence in cyclic fatigue resistance of rotary files. Methods: K3 Endo (group K) and EndoSequence (group E) files, 25/.04, 25 mm, were subdivided into 3 subgroups (n=12) according to the number of uses, 1, 3 and 5 uses, totalizing 72 files. The files were submitted to dynamic assays device moved by an electric engine, using 300 rpm of speed that permitted the reproduction of pecking motion. The files run within a temperate steel ring’s groove, simulating an instrumentation of a curved root canal with 40-degrees and 5-mm of curvature radius. The fracture of file was detected by sensor of device and the time and the number of cycles was acquired. The data were analyzed statistically by two-way ANOVA (p<0.05). Results: There were no statistical significant differences in regard to the number of uses (p>0.05). K3 Endo files showed greater resistance to cyclic fatigue than EndoSequence instruments (p<0.01). Conclusion: It may be concluded that the cross-section of instruments presented significant influence in cyclic fatigue resistance and the number of uses up to 5 times had no influence in cyclic fatigue resistance in both NiTi rotation systems evaluated.

2019 ◽  
Vol 13 (1) ◽  
pp. 57-60
Author(s):  
Damla Özsu Kırıcı ◽  
Ertuğrul Karataş ◽  
Ahmet Demirhan Uygun ◽  
Ezgi Doğanay Yıldız ◽  
Kezban Meltem Çolak ◽  
...  

Background. The aim of the present study was to compare the cyclic fatigue resistance of novel nickel titanium rotary pathfinding instruments. Methods. Twenty instruments were selected for each file system. A simulated stainless steel root canal, with a 90° angle of curvature and a curvature radius of 3 mm, was used for cyclic fatigue test of the ProGlider (#16, progressive taper: 0.02‒ 0.085), PathGlider (#15, taper: .03), and One G (#14, taper: .03) instruments. Statistical analyses were performed with oneway ANOVA (P=0.05). Post hoc Tukey tests were used to determine any statistically significant differences between the groups. Results. The ProGlider instruments exhibited significantly more cyclic fatigue resistance than both PathGlider and One G instruments (P<0.001). One G instruments had significantly more resistance to fracture than PathGlider instruments (P<0.05). Conclusion. ProGlider instruments had better cyclic fatigue resistance than PathGlider and One G instruments.


2018 ◽  
Vol 12 (3) ◽  
pp. 208-212 ◽  
Author(s):  
Mehmet Adiguzel ◽  
Ipek Isken ◽  
Ismail Ilker Pamukcu

Background. The aim of this study was to compare the cyclic fatigue resistance of XP-endo Shaper, HyFlex CM, FlexMaster and Race rotary instruments at body temperature (37±1°C). Methods. Twenty XP-endo Shaper (#30/.01), 20 HyFlex CM (#30/.04), 20 FlexMaster (#30/.04) and 20 Race (#30/.04) instruments were tested at body temperature (n=20). The instruments were evaluated in artificial canals with a 3-mm radius of curvature and 60° angle of curvature to the center of the 1.5-mm-wide canal. Each instrument was rotated until fracture occurred and the number of cycles to failure (NCF) recorded. Data were analyzed using one-way ANOVA and Tukey HSD tests (P<0.05). Results. The difference in the NCF of all the instruments was statistically significant (P<0.05). The order of the instruments from the highest to the lowest NCF was as follows: XP-endo Shaper (3064.0±248.1), HyFlex CM (1120.5±106.1), FlexMaster (569.8±48.4) and Race (445.5±53.5). Conclusion. Under the limitations of the present study, XP-endo Shaper instruments were more resistant to cyclic fatigue than the #30/.04 nickel-titanium rotary instruments immersed in water at simulated body temperature.


2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Pooja D. Khandagale ◽  
Prashant P. Shetty ◽  
Saleem D. Makandar ◽  
Pradeep A. Bapna ◽  
Mohmed Isaqali Karobari ◽  
...  

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.


2020 ◽  
Vol 46 (3) ◽  
pp. 431-436 ◽  
Author(s):  
Eugenio Pedullà ◽  
Giusy Rita Maria La Rosa ◽  
Chiara Virgillito ◽  
Ernesto Rapisarda ◽  
Hyeon-Cheol Kim ◽  
...  

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2256
Author(s):  
Giusy Rita Maria La Rosa ◽  
Valeria Shumakova ◽  
Gaetano Isola ◽  
Francesco Indelicato ◽  
Calogero Bugea ◽  
...  

Background: To compare the influence of different temperatures and curvature radii on the cyclic fatigue resistance of F6 SkyTaper (F6ST) and One Curve (OC) single file nickel-titanium rotary instruments. Methods: A total of 120 instruments of F6ST and OC #25.06 were evaluated in 5 mm and 3 mm curvature radii at two temperatures (20 °C ± 1 °C and 37 °C ± 1 °C) in 16 mm stainless steel artificial canals associated with a curvature of 60°. The cyclic fatigue of tested files was assessed by employing a customized testing apparatus and expressed as times to fracture (TtF). A statistical analysis was performed with the significance level set at 95%. Results: All instruments decreased their TtF at 37 °C except for OC in the 3 mm radius, in which no significant difference was detected between 20 °C and 37 °C. A 3 mm curvature radius negatively affected TtF of all tested instruments, except for F6ST at 20 °C. F6ST had higher TtF than OC in the 3 mm radius at 20 °C, with no significant difference between them in the other tested conditions. Conclusions: Under the limits of the present in vitro study, body temperature impaired cyclic fatigue resistance of all files, except for OC in the 3 mm curvature radius. All instruments exhibited lower times to fracture in the 3 mm radius, excluding F6ST at 20 °C.


2020 ◽  
Vol 14 (2) ◽  
pp. 111-115 ◽  
Author(s):  
Gülsah Uslu ◽  
Mustafa Gündoğar ◽  
Taha Özyürek ◽  
Gianluca Plotino

Background. This study was conducted to compare the cyclic fatigue resistance of VDW.ROTATE,TruNatomy Prime, HyFlex CM, and 2Shape nickel-titanium (NiTi) rotary instruments in doublecurvedcanals in a simulated clinical environment. Methods. Eighty NiTi files were used for the fatigue testing in stainless steel canals compatible withinstrument sizes until fracture occurred (n=20): VDW.ROTATE (04./25#), TruNatomy Prime (04./26#),HyFlex CM (04./25#) and 2Shape TS04./25#( 1). For each instrument, the number of cycles to fracture(NCF) was calculated, and the fractured fragment length (FL) was measured. To verify that the fileswere fractured due to cyclic fatigue, the fractured surfaces of the files were evaluated under a scanningelectron microscope. Data were statistically analyzed using the Kruskal–Wallis and Student’s t-tests atthe %95 confidence level. Results. The failure of the files due to cyclic fatigue was first seen in the apical curvature before thecoronal curvature (P<0.05). The highest fatigue resistance was observed in VDW.ROTATE and HyFlexCM files in both curvatures (P<0.05). There were no significant differences in the fatigue resistancebetween the HyFlex CM and VDW.ROTATE files or between the 2Shape and the TruNatomy files(P>0.05). There was no difference in the fractured lengths of the files between the apical and coronalcurvatures (P>0.05). Conclusion. In artificial S-shaped root canals, VDW.ROTATE and HyFlex CM files exhibited higherfatigue resistance compared to 2Shape and TruNatomy files.


2021 ◽  
Vol 11 (Suppl. 1) ◽  
pp. 114-121
Author(s):  
Mehmet Dundar ◽  
Özkan Adıgüzel ◽  
Sadullah Kaya

Aim: Root canal preparation is one of the most important steps of root canal treatment. Preparation procedure includes disinfection and shaping protocols. Ni-Ti rotary file systems are usually used for shaping. The biggest disadvantage of the usage of Ni-Ti rotary file systems is that the file gets broken during the treatment. There are many reasons for the breakage of files. One of the reasons may be the increase in the access angle. The purpose of this study is to compare the cyclic fatigue of reciprocating Reciproc and WaveOne Gold rotary systems according to different angles of accessing the root canal of Ni-Ti files. Methodology: In our study, 90 root canal files were used, 45 of which is Reciproc R25 (VDW GmbH, Munich, Germany) and the other 45 of which is WaveOne Gold Primary 25/07 (Dentsply, Maillefer, Ballaigues, Switzerland). Specially designed and manufactured stainless steel artificial roots whose curvature angle is 60° and curvature radius is 5 mm, which replicates the clinical conditions, were arranged. By enabling the files access the roots at 0°- 15°- 30° degrees, the lap numbers that they do till they break due to cyclic fatigue were examined. Results: When looking at the lap numbers that the Reciproc and WaveOne Gold root canal files do till they break, at accessing the roots at the same angles WaveOne Gold root canal file makes more lap numbers at all angles when compared with the Reciproc root canal file. Significant results were found when the groups were compared within one another and between groups and among all numeric data in the statistical analysis performed. It was also found that WaveOne Gold root canal file had more cyclic fatigue resistance. When the groups were compared within one another, it was found that the increase in the root access angle decreases the cyclic fatigue resistance of the files (p<0.05). No significant difference was found in the statistical analysis for comparison of the length of the broken file pieces (p=0.01). It was analyzed that when the broken files were examined via scanning electron microscope, file breakages occurred due to cyclic fatigue. Conclusion: Not only do the design features and production technology affect the breakage resistance due to cyclic fatigue of the root canal, the access angle to the roots affects the cyclic fatigue of the root canal files, as well.   How to cite this article: Adıgüzel Ö, Dundar M, Kaya S. The comparison of cyclic fatigue resistance of two different reciprocal files according to different entry angles into the root canal. Int Dent Res 2021;11(Suppl.1):114-21. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.18   Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.


Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5823
Author(s):  
Saulius Drukteinis ◽  
Vytaute Peciuliene ◽  
Ruta Bendinskaite ◽  
Vilma Brukiene ◽  
Rasmute Maneliene ◽  
...  

The better understanding of the clinically important behavioral features of new instrument systems has an important significance for the clinical endodontics. This study aimed to investigate the shaping and centering ability as well as cyclic fatigue resistance of HyFlex CM (CM), HyFlex EDM (EDM) and EdgeFile (EF) thermally treated nickel–titanium (NiTi) endodontic instrument systems. Sixty curved root canals of the mesial roots of mandibular molars were randomly assigned into three groups (n = 20) and shaped using CM, EDM and EF files up to the size 40 and taper 04 of the instruments. µCT scanning of the specimens before and after preparation was performed and the morphometric 2D and 3D parameters were evaluated in the apical, middle and coronal thirds of root canals. In each group, 40.04 instruments (n = 20) were subjected to the cyclic fatigue resistance test in artificial root canals at 37 °C temperature until fractures occurred, and the number of cycles to failure (NCF) was calculated. The fractographic analysis was performed using a scanning electron microscope, evaluating topographic features and surface profiles of the separated instruments. The one-way analysis of variance with post hoc Tuckey’s test was used for statistical analysis of the data; the significance level was set at 5%. All systems prepared the comparable percentage of root canal surface with the similar magnitude of canal transportation in all root thirds (p > 0.05), but demonstrated significantly different resistance to cyclic fatigue (p < 0.05). The most resistant to fracture was EF, followed by EDM and CM. The length of the fractured fragments was not significantly different between the groups, and fractographic analysis by SEM detected the typical topographic features of separated thermally treated NiTi instrument surfaces.


2018 ◽  
Vol 12 (4) ◽  
pp. 283-287 ◽  
Author(s):  
Gülşah Uslu ◽  
Taha Özyürek ◽  
Mustafa Gündoğar ◽  
Koray Yılmaz

Background. The aim of this study was to compare the cyclic fatigue resistance of 2Shape, Twisted File (TF) and EndoSequence Xpress (ESX) nickel-titanium rotary files at intracanal temperature (35°C). Methods. Twenty 2Shape TS1 (25/.04), 20 TF (25/.04) and 20 ESX (25/.04) files were tested for cyclic fatigue at intracanal temperature (35°C). All the instruments were rotated in artificial canals which were made of stainless steel with an inner diameter of 1.5 mm, 60° angle of curvature and a radius curvature of 5 mm until fracture occurred; the time to fracture was recorded in seconds using a digital chronometer and the number of cycles to fracture (NCF) for each file was calculated. Kruskal-Wallis test with Bonferroni correction was performed to statistically analyze data using SPSS 21.0. Statistical significance was set at P<0.05. Results. NCF values revealed that the 2Shape had significantly the highest cyclic fatigue resistance, followed by TF and ESX at intracanal temperature (P<0.05). The difference was significant between the TF and ESX groups (P<0.05). There was no significant difference among the 2Shape, TF and ESX files with respect to the lengths of the fractured file fragments (P>.05). Conclusion. Within the limitations of present study, it was concluded that the cyclic fatigue resistance of 2Shape files at the intracanal temperature is higher than that of TF and ESX files.


2021 ◽  
Vol 11 (Suppl. 1) ◽  
pp. 67-73
Author(s):  
Ahmet Akay ◽  
Özkan Adıgüzel ◽  
Seda Erkan Akay ◽  
Sadullah Kaya

Aim: The purpose of this in vitro study is to compare the cyclic fatigue resistance of Reciproc Nickel-Titanium (Ni-Ti) rotary files while operating root canals using in three different reciprocal angles. Methodology: Forty-five pieces of Reciproc R25 canal files were tested using artificial canals with a 60° angle of curvature, 5 mm curvature radius, and 1.5 mm diameter carved into a stainless steel block. The Ni-Ti files were checked with a stereomicroscope and then randomly separated into 3 groups. Group 1 consisted of reciprocal angles CCW 150°–CW 30°, Group 2 consisted of CCW 180°–CW 60°, and Group 3 consisted of CCW 210°–CW 90°. The duration of the cyclic fatigue being measured, elapsed time until a file fractured was determined with a chronometer. The lengths of the fractured pieces were measured with a digital caliper. After the cyclic fatigue test, two samples from each group were examined with a Scanning Electron Microscope (SEM) to determine the signs of cyclic fatigue. Results: One-way analysis of variance (ANOVA) was applied to the normally distributed groups (p<0,05). Since there was a significant statistical difference of file’s cyclic fatigue resistance (p=0,001) between the groups, Tukey’s honestly significant difference (HSD) post-hoc pairwise comparison test were used for determine to between which groups. While there were statistically significant differences between Group 1 and Group 2 (p=0,001), and between Group 1 and Group 3 (p=0,001), there was no significant difference between Group 2 and Group 3 (p=0,376). Group 1 displayed the highest resistance to cyclic fatigue. There were no statistically significant differences between the lengths of the fractured files within the three groups according to the one-way analysis of variance (p=0,847). Conclusion: In our study, it was observed that the reciprocal angles of CCW 150°–CW 30°, which were also suggested by the file manufacturer firms, had the highest fracture resistance against cyclic fatigue.   How to cite this article: Akay A, Adıgüzel Ö, Erkan Akay S, Kaya S. Comparison of cyclic fatigue of a reciprocating file system at different angles of rotation. Int Dent Res 2021;11(Suppl.1):67-72. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.11   Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.  


Sign in / Sign up

Export Citation Format

Share Document