Comprehensive Characterization of Blue Wire NiTi File Failure: A Comparative Analysis of Cyclic Fatigue and Torsional Resistance Properties

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

1. In Abstract, what does the variable p mean?

2. Numerous relevant papers have been published in 2024 and 2023. Some key, important or/and latest research results in this topic should be discussed and cited, such as:

[1] Zhang Y, Guo W, Shi J, et al. Improved rotating bending fatigue performance of laser directed energy deposited Ti6Al4V alloys by laser shock peening[J]. Journal of Alloys and Compounds, 2024, 980: 173664.

[2] Chen P, Cai X, Liu Y, et al. Combined effects of grain size and training on fatigue resistance of nanocrystalline NiTi shape memory alloy wires[J]. International Journal of Fatigue, 2023, 168: 107461.

[3] Oh S, Kim T H, Chang S W. Mechanical Properties of NiTi Rotary Files Fabricated through Gold-Wire, CM-Wire, T-Wire, and R-Phase Heat Treatment[J]. Applied Sciences, 2023, 13(6): 3604.

3. In Figure 1, please mark the name of each component.

4. Please add detailed descriptions of Figures 2 and 3

Comments on the Quality of English Language

Moderate editing of English language required

Author Response

It is an immense pleasure to submit our revised manuscript entitled: “Comprehensive Characterization of Blue Wire NiTi File Failure: A Comparative Analysis of Cyclic Fatigue and Torsional Resistance Properties”.

We would like to thank all reviewers for their time spent reviewing the manuscript and the constructive comments provided. We made sure that each one of the reviewers’ comments has been considered and the manuscript is revised accordingly. All amendments and/or additions are highlighted in yellow.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This paper provides a detailed analysis of the cyclic fatigue and torsional resistance properties of two blue heat-treated nickel titanium (NiTi) file systems, Tia Tornado Blue (TTB) and Race Evo (RE), commonly used in root canal preparation. The study reveals that the RE files exhibit superior cyclic fatigue resistance compared to TTB files, regardless of the solution type used. Additionally, TTB files demonstrate better torsional fatigue resistance than RE files. Energy-dispersive X-ray spectroscopy (EDX) analysis was conducted to assess the elemental composition of the files, shedding light on how these properties influence their mechanical behavior. The findings offer valuable insights for enhancing root canal instrumentation techniques in dental practice, emphasizing the importance of understanding the material characteristics of NiTi files for optimizing their performance and durability during endodontic procedures. Some revisions are recommended.

1. Can you elaborate on the specific parameters used for cyclic fatigue testing, such as rotational speed, number of cycles to fracture, and the artificial metal canal setup, to provide a clearer understanding of the testing conditions?

2. How was the simulated body temperature maintained during the torsional fatigue testing, and were there any considerations given to temperature fluctuations that could affect the mechanical properties of the NiTi files?

3. Could you explain the rationale behind choosing sodium hypochlorite and saline solutions as the immersion media for cyclic fatigue testing and how these solutions simulate clinical conditions?

4. What methods were employed to measure the length of fractured segments in the torsional fatigue testing, and how was this measurement standardized to ensure accuracy and reliability?

5. Were there any observations or differences in the elemental composition of the NiTi files between the Tia Tornado Blue (TTB) and Race Evo (RE) systems that could explain their varying fatigue resistance properties?

6. How was the torque at failure recorded during the torsional fatigue testing, and were there any factors considered that could influence the torque measurements, such as file design or surface characteristics?

7. Can you provide insights into the statistical analysis conducted to compare the cyclic fatigue resistance of the TTB and RE files, including the significance level used and any adjustments made for multiple comparisons?

8. Were there any visual or microscopic observations made during the testing that could further support the differences in fatigue resistance between the TTB and RE files, such as surface morphology changes or crack propagation patterns?

9. Did the study investigate the effect of repeated sterilization cycles on the fatigue properties of the NiTi files, considering that autoclave sterilization can impact the material properties of NiTi instruments?

10. How did the alternating file blade design of the RE system contribute to its superior cyclic fatigue resistance compared to the TTB system, and were there any structural analyses conducted to assess the impact of this design on fatigue performance?

11. Were there any considerations given to the potential influence of operator variability or human factors on the testing outcomes, and how were these factors controlled or minimized during the experimental procedures?

12. Can you discuss any limitations or challenges encountered during the study that may have affected the interpretation of the results, and how these limitations could be addressed in future research to enhance the validity and generalizability of the findings?

Comments on the Quality of English Language

Minor editing of English language required

Author Response

It is an immense pleasure to submit our revised manuscript entitled: “Comprehensive Characterization of Blue Wire NiTi File Failure: A Comparative Analysis of Cyclic Fatigue and Torsional Resistance Properties”.

We would like to thank all reviewers for their time spent reviewing the manuscript and the constructive comments provided. We made sure that each one of the reviewers’ comments has been considered and the manuscript is revised accordingly. All amendments and/or additions are highlighted in yellow.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript discusses the mechanical properties of blue wire NiTi files and I found the work interesting but it needs some improvements which are listed below:

Concerning the format use justified margins.

In Materials and Methods between line 101 and 105 there are more quantities but without dimensions so their establishment needs careful checking.

Also in the above paragraph write 13.6× magnification.

More details should be added to describe what is Type 1 error.

It is not clear how was it possible to examine the effect of NaOCl and saline solution if the files were fixed in an artificial metal canal.

Comments on the Quality of English Language

Quality of English is basically good, but in the legends of Fig. 2 and 3 I recommend to begin "Part (a) shows..." and close up with the next sentence "striations, while" and "mark, while". They sound better in this way.

Author Response

It is an immense pleasure to submit our revised manuscript entitled: “Comprehensive Characterization of Blue Wire NiTi File Failure: A Comparative Analysis of Cyclic Fatigue and Torsional Resistance Properties”.

We would like to thank all reviewers for their time spent reviewing the manuscript and the constructive comments provided. We made sure that each one of the reviewers’ comments has been considered and the manuscript is revised accordingly. All amendments and/or additions are highlighted in yellow.

Author Response File: Author Response.pdf