Effect of Temperature of Sodium Hypochlorite on Cyclic Fatigue Resistance of Heat-treated Reciprocating Files

Abstract Objective The aim of this study was to investigate the effect of additional apical preparation using the ProDesign Logic (PDL) 50/.01 rotary heat-treated nickel–titanium (NiTi) file with a larger diameter and minimal taper for retreatment of curved root canals. Materials and Methods Mesial curved root canals of 12 mandibular molars were prepared using PDL 25/.06 and filled using the continuous wave of condensation technique and AH Plus sealer. After retreatment using ProDesign S (PDS) 25/.08, PDL 25/.06 and PDL 35/05, a complementary procedure was performed with PDL 50/.01. Microcomputed tomography (micro-CT) scanning was performed before and after retreatment procedures. The cyclic fatigue resistance of unused PDS 25/.08, PDL 25/.06, PDL 35/.05 and PDL 50/.01 instruments (n = 12) was evaluated in a stainless-steel device. Statistical Analysis Data on the volumes of the root canals and the remaining filling materials were submitted to the paired t-test. Cyclic fatigue resistance data was submitted to one-way ANOVA and Tukey’s tests (α = 0.05). Results Use of PDL 50/.01 decreased the remaining filling materials in the apical third (p < 0.05). The root canal volume was similar in the cervical and middle thirds before and after preparation using PDL 50/.01 (p > 0.05). PDL 50/.01 presented the highest cyclic fatigue resistance (p < 0.05). Conclusions Use of the PDL 50/.01 instrument as an additional apical preparation for retreatment of curved root canals improved filling material removal in the apical third, while maintaining the dentin in the cervical and middle thirds. In addition, PDL 50/.01 presented high-flexural resistance.

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Effect of immersion in sodium hypochlorite on the cyclic fatigue resistance of three rotary instruments

Journal of Conservative Dentistry ◽

10.4103/jcd.jcd_117_19 ◽

2020 ◽

Vol 23 (6) ◽

pp. 554

Author(s):

AnaGrasiela Da Silva Limoeiro ◽

Daiane Nogueira ◽

CarlosEduardo Da Silveira Bueno ◽

AugustoShoji Kato ◽

AlexandreSigrist De Martin ◽

...

Keyword(s):

Fatigue Resistance ◽

Sodium Hypochlorite ◽

Cyclic Fatigue ◽

Rotary Instruments

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Influence of Different Heat Treatments on Torsional and Cyclic Fatigue Resistance of Nickel–Titanium Rotary Files: A Comparative Study

Applied Sciences ◽

10.3390/app10165604 ◽

2020 ◽

Vol 10 (16) ◽

pp. 5604 ◽

Cited By ~ 2

Author(s):

Gianluca Gambarini ◽

Andrea Cicconetti ◽

Dario Di Nardo ◽

Gabriele Miccoli ◽

Alessio Zanza ◽

...

Keyword(s):

Heat Treatment ◽

Fatigue Resistance ◽

Cyclic Fatigue ◽

Sem Analysis ◽

Nickel Titanium ◽

Torsional Resistance ◽

Heat Treated ◽

Torsional Test ◽

Time To Fracture ◽

Flexural Resistance

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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Impact of Peracetic Acid on the Dynamic Cyclic Fatigue of Heat-Treated Nickel-Titanium Rotary Endodontic Instrument

International Journal of Dentistry ◽

10.1155/2021/6676005 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Suhad Jabbar Hamed Al-Nasrawi ◽

Zuha Ayad Jaber ◽

Nibrass Talib Al-Quraine ◽

Abtesam Imhemed Aljdaimi ◽

Sattar Jabbar Abdul-Zahra Al-Hmedat ◽

...

Keyword(s):

Fatigue Resistance ◽

Peracetic Acid ◽

Cyclic Fatigue ◽

Nickel Titanium ◽

Control Group ◽

Heat Treated ◽

Respective Control Group ◽

Before And After ◽

Number Of Cycles ◽

The Impact

Peracetic acid (PAA) is widely used as a sterilizing/disinfecting agent, and, in endodontics, it has been introduced as a promising irrigant in root canal treatment. It has been used at different concentrations to achieve various functions. However, endodontic instruments in contact with PAA of a certain concentration may affect their fatigue resistance. Therefore, the aim of this study was to investigate the impact of PAA on the cyclic fatigue resistance of three commercial heat-treated nickel-titanium (NiTi) rotary files. Three types of heat-treated NiTi rotary files were selected: One Curve (OC), ProTaper Gold (PTG), and Wave One Gold (WOG). Each type was divided into three subgroups (n = 6 for each file type): (1) untreated instruments; (2) files immersed in 0.002% PAA; and (3) files immersed in 0.35% PAA. The performance of each file type was tested in a simulated canal. The number of cycles to fracture (NCF) was determined to assess cyclic fatigue resistance of the files. Independent sample t-test was applied to compare each treated file within a subgroup with its respective control group, and one-way ANOVA was used for comparison among the main groups. All types of tested files revealed a significant decline in the cyclic fatigue resistance after exposure to 0.002% PAA except the PTG ( P = 0.209 ). After exposure of the files to a higher concentration (0.35% PAA), a dramatic reduction was demonstrated by all the groups. Before and after exposure of the files to PAA, PTG displayed the highest cyclic fatigue resistance, followed by the WOG, while the OC showed the lowest resistance. Exposure of heated-treated NiTi files to PAA in a relatively high or low concentration adversely affects the cyclic fatigue resistance. The PTG files demonstrated the best performance among the tested types and can be disinfected with 0.002% PAA for clinical purpose.

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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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Cyclic Fatigue Resistance of Blue Heat-Treated Instruments at Different Temperatures

International Journal of Biomaterials ◽

10.1155/2021/5584766 ◽

2021 ◽

Vol 2021 ◽

pp. 1-5

Author(s):

Thalita Miranda Vieira ◽

Ryhan Menezes Cardoso ◽

Nayane Chagas Carvalho Alves ◽

Silvio Emanuel Acioly Conrado de Menezes ◽

Shirley Machado Batista ◽

...

Keyword(s):

Stainless Steel ◽

Fatigue Resistance ◽

Cyclic Fatigue ◽

Significance Level ◽

Instrument Type ◽

Heat Treated ◽

Different Temperatures ◽

Vortex Blue ◽

Student’S T ◽

Student’S T Test

The main aim is to evaluate the cyclic fatigue resistance of blue heat-treated instruments with different kinematics. Twenty-four endodontic instruments of the same brand were used for each of three experimental groups: VB (Vortex Blue 40/0.04), RB (RECIPROC Blue 40/0.06), and XB (X1 Blue 40/0.06). The instruments were randomly distributed and subjected to temperatures of 20°C and 37°C. The fatigue test was performed using a stainless steel device. Data were analysed using the Shapiro–Wilk test, Student’s t-test, the F test, and Tukey’s and Tamhane tests at significance level P = 0.05 . The instruments’ cyclic fatigue resistance at both temperatures differed significantly for each instrument type ( P < 0.001 ). The RB instruments displayed greater cyclic fatigue resistance at the tested temperatures compared with the VB and XB instruments ( P < 0.001 ). Reciprocating kinematics positively influenced cyclic fatigue resistance. Blue heat-treated instruments showed decreased cyclic fatigue resistance as the temperature increased ( P < 0.001 ).

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