Varying the Polishing Protocol Influences the Color Stability and Surface Roughness of Bulk-Fill Resin-Based Composites

Round 1

Reviewer 1 Report

In the manuscript entitled: “Varying the polishing protocol influences the color stability and surface roughness of bulk-fill resin- based composites” the authors evaluate the surface roughness of two bulk- fill resin composites, after being submitted to different polishing procedures, as well as their color change after immersion in a coffee solution, comparing them to traditional incremental-fill hybrid resin composite.

The authors found that resin composite type, polishing procedure, and their interaction had a statistically significant effect on surface roughness and color change . Fill-Up™ exhibited the highest surface roughness and greatest color change. Differences in color change were statistically significant. Filtek™ Bulk Fill registered the lowest surface roughness and color change, after the three- step polishing procedure.

The authors concluded that surface roughness and color change are material-dependent and also depend upon the polishing procedure. Higher surface roughness relates to greater color changes.

Major comments:

In general, the idea and innovation of this study, regards the analysis of influencers of surface roughness of bulk-fill resin- based composites is interesting, because even if the analysis of these factors in composite restoration was already validated but further studies on this topic could be an innovative issue in this field could be open an innovative matter of debate in literature by adding new information. Moreover, there are few reports in the literature that studied this interesting topic with this kind of study design.

The study was well conducted by the authors; However, there are some concerns to revise that are described below.

The introduction section resumes the existing knowledge regarding the important factor linked with surface roughness of bulk-fill resin- based composites.

However, as the importance of the topic, the reviewer strongly recommends, before a further re-evaluation of the manuscript, to update the literature through read, discuss and must cites in the references with great attention all of those recent interesting articles, that helps the authors to better introduce and discuss the aim of the study in light of periodontal biofilm released during periodontal inflammation that could interfere with surface roughness: 1) Isola G, Alibrandi A, Currò M, Matarese M, Ricca S, Matarese G, Ientile R, Kocher T. Evaluation of salivary and serum ADMA levels in patients with periodontal and cardiovascular disease as subclinical marker of cardiovascular risk. J Periodontol. 2020, 91;8:1076-84. doi: 10.1002/JPER.19-0446. 2) Isola G, Polizzi A, Alibrandi A, Williams RC, Leonardi R. Independent impact of periodontitis and cardiovascular disease on elevated soluble urokinase-type plasminogen activator receptor (suPAR) levels. J Periodontol. 2020 Oct 22. doi: 10.1002/JPER.20-0242. 3) Isola G, Polizzi A, Patini R, Ferlito S, Alibrandi A, Palazzo G. Association among serum and salivary A. actinomycetemcomitans specific immunoglobulin antibodies and periodontitis. BMC Oral Health. 2020 Oct 15;20(1):283. doi: 10.1186/s12903-020-01258-5.

The authors should be better specified, at the end of the introduction section, the rational of the study and the aim of the study. In the material and methods section, should better clarify the polishing brush SHP Soft Bristle Brush and the color stability determination.

The discussion section appears well organized with the relevant paper that support the conclusions, even if the authors should better discuss the importance of gingival biofilm that could be involved with the surface retraction of composites. The conclusion should reinforce in light of the discussions.

In conclusion, I am sure that the authors are fine clinicians who achieve very nice results with their adopted protocol. However, this study, in my view, does not in its current form, satisfy a very high scientific requirement for publication in this journal and requests a revision before a further re-evaluation of the manuscript.

Minor Comments:

Abstract:

• Better formulate the introduction section by better describing the background

Introduction:

• Please refer to major comments

Discussion

• Please add a specific sentence that clarifies the results obtained in the first part of the discussion
• Page 9 last paragraph: Please reorganize this paragraph that is not clear

Author Response

Please see the attachment.

We kindly thank you for your comments and suggestions.

Author Response File: Author Response.pdf

Reviewer 2 Report

Dear authors,

This is a review on the paper entitled “Varying the polishing protocol influences the color stability and surface roughness of bulk-fill resin based composites” by Filipa Freitas, Teresa Pinheiro de Melo, António HS Delgado, Paulo Monteiro, João Rua, Luís Proença, Jorge Caldeira, Ana Mano Azul, José João Mendes, submitted for J. Funct. Biomater, manuscript number materials-1003922.

The authors focused on presenting the evaluation of the surface roughness of bulk fill resin composites, after being submitted to different polishing procedures, as well as their color change after immersion in a coffee solution, comparing them to traditional incremental-fill hybrid resin composite. Furthermore, the correlation of roughness and color stability according to the composites and polishing protocols that were evaluated, are also studied.

The paper fits to the journal field.

In my opinion the presented study is a good approach. The paper is very well written and described.

Abstract

• Needs no reformulation but maybe could be shortened.

The introduction part

• is quite good, minor English control is required. 

The experimental procedure

Materials

• maybe the exact chemical composition (and or composition of different oxides) and method of determination for the materials should be provided.

Methods

• The methods and the set-up used in the research is well described.

Results

• Are well described

Discussions

• It discusses all the findings compared to other findings from different research, in a good manner.

Conclusion

• Supported by the results.

References

• no comments.

Author Response

Please see the attachment.

We kindly thank you for your comments and suggestions.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors have revised and solved all comments raised by the reviewer.