the aim is clear 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)

The tittle is informative and relevant Cyclic Fatigue Comparison of TruNatomy, Twisted File, and ProTaper Next Rotary Systems

The references are 1. Relevant 2.13 of 22 references are over 5 years old 3. Referenced correctly 4.there are no Key studies included

It is clear what is already known about this topic One of the primary concerns in the practice of endodontics is the separation of rotary instrument as a result of cyclic fatigue, particularly in root canals with severe curvatures. The nickel-titanium (NiTi) instrument cyclic fatigue is influenced by various factors

the research question is clearly outlined The aim of this work is to assess the cyclic fatigue re- sistance of this newly released system and to compare it with familiar rotary file systems (ProTaper Next and Twisted Files).

The research question is justified given what is already known about the topic

The process of subject selection is clear Forty-five NiTi files were distributed into 3 different groups (n = 15 per group).

inclusion criteria: All files have the same length (25 mm)

Exclusion criteria none

The variables are defined and measured appropriately Every file was rotated at 300 rpm rotational speed until it is separated inside the artificial stainless-steel canal. The required time for separation was recorded in seconds. Afterwards, the number of cycles to fracture (NCF) was calculated by multiplying the time required (in seconds) to failure by rotational speed The study methods are valid and reliable Pain assessed by the visual analog scale

There is enough detail in order to replicate the study Forty-five NiTi files were distributed into 3 different groups (n = 15 per group). Group 1 consists of PTN X2 with tip size 25 and 0.06 taper, group 2 consists of TF instrument with tip size 25 and 0.06 taper, and group 3 consists of TN Prime File with tip size 26 and 0.04 taper

The data is not all presented in an appropriate way ● Tables and figures relevant and clearly presented ==> there is no figure ● Appropriate units, rounding, and number of decimals ● Titles, columns, and rows labelled correctly and clearly ● Categories grouped appropriately

There is no repetitive the text in the results add to the data

I am clear about what is a statistically significant result ANOVA showed a statistically significant difference (p < 0.05). Tukey’s multiple comparison test (Table 1) showed that PTN had the least NCF compared with TF (p < 0.05) and TN (p < 0.05). Moreover, TN on average had the highest NCF compared with PTN (p < 0.05) and TF (p < 0.05).

I am clear about what is a practically meaningful result

The results are discussed from multiple angles and placed into

context without being overinterpreted

The conclusions answer the aims of the study

The aim of this work is to assess the cyclic fatigue re- sistance of this newly released system and to compare it with familiar rotary file systems (ProTaper Next and Twisted Files).

The conclusion is The TruNatomy system has a superior cyclic fatigue resis- tance compared with the TF and PTN file systems. TF is significantly more resistant to fatigue compared with PTN.

The conclusions are supported by references or results

By references: the fact that the TruNatomy file is made of a thin NiTi wire (0.8 mm) might have resulted in increasing cyclic fatigue resistance By result: it might be speculated that this design compared with PTN rectangular cross section and the TF equilateral triangular cross section could con- tribute to the higher cyclic fatigue resistance of the TN files.

The limitations of the study are not fatal and they are opportunities to inform future research

Limitation of the study: none

To inform future research future studies are required to evaluate other properties of this file and to examine its clinical performance.