Ion Release from Dental Implants, Prosthetic Abutments and Crowns under Physiological and Acidic Conditions

Round 1

Reviewer 1 Report

The reviewed article presents the results of studies on ion release from a dental implant and filling. Understanding the mechanism of this process has a direct impact on osseointegration and implant life. The studies were conducted in accordance with the relevant ISO standards, which were modified to simulate oral fluid exchange. In conclusions, the authors indicate that both the surface treatment, anodizing on implants and prosthetic abutments, as well as the immersion medium, influence the release of ions.

The paper requires the following amendments:

1. Introduction:
   Authors should clearly define the elements of novelty of the received results in comparison to the previous literature reports.
2. Materials and Methods:
   Genaral remark: Beside information of the reagents used, ready-made tests, and applied measuring equipment also information of manufacturer, city and country should also be provided. These are the Editor's requirements.
3. Table 1: How was metallic alloys composition determined?
4. Details of the anodizing process should be added.
5. Hanks' solution: If a ready-made solution was used, the information about the manufacturer should be given, but if the solution was prepared, the composition of the solution should be given.
6. Discussion:
   line 220; "These results differ from those of other studies...." What are these differences? What are they important for the use of the studied implants?
7. Conclusions:
   What conclusions are due to the fact that ions of elements with proven toxic effect are released both in the Hanks environment; solution and Lactic acid solution?
   Information about the manner of the presented test results use should be added.

In my opinion, the reviewed manuscript can be accepted to publication after major revision.

Author Response

Response to Reviewer 1 Comments

REVIEWER #1:

1. Introduction: Authors should clearly define the elements of novelty of the received results in comparison to the previous literature reports.

In order to introduce our novelty, some lines were added at the end of this section.

2. Materials and Methods: Genaral remark: Beside information of the reagents used, ready-made tests, and applied measuring equipment also information of manufacturer, city and country should also be provided. These are the Editor's requirements.

City and country have been provided for all the manufacturers.

3. Table 1: How was metallic alloys composition determined?

This composition according the different standards (ISO 5832-2:2018, ISO 5832-3:2016 and ISO 22674:2006) were introduced as a matter of reference. This has been clarified in the manuscript.

4. Details of the anodizing process should be added.

The anodizing process has been explained in more detail in the manuscript.

5. Hanks' solution: If a ready-made solution was used, the information about the manufacturer should be given, but if the solution was prepared, the composition of the solution should be given.

It was a commercially available solution and, therefore, the manufacture have been indicated.

6. Discussion: line 220; "These results differ from those of other studies...." What are these differences? What are they important for the use of the studied implants?

These differences referred to the vanadium release: vanadium release was similar in physiological and acidic conditions, but other studies reported higher release of this ion in acidic conditions. The sentence has been updated to increase its understanding.

7. Conclusions: What conclusions are due to the fact that ions of elements with proven toxic effect are released both in the Hanks environment; solution and Lactic acid solution? Information about the manner of the presented test results use should be added.

Conclusions have been completed with the reviewer’s comments.

Reviewer 2 Report

This is an interesting study on the release of ions from implant prosthetic restorations depending on various factors.

Some criticisms are present:

1. The title is misleading because anodizing is only an observed mechanism while the focus of the work is the ionic release from different implant and prosthetic solutions

2. Line 12 insert “prosthetic” restoration

3. A missing part of the introduction is that relating to the potential effects of cytotoxicity of various dental materials, a much debated topic in the scientific literature of recent years. In this regard, I suggest to insert, in the reference section and in the discussion, the following scientific work which could help the reader in understanding the problem:

Pagano S, Coniglio M, Valenti C, Negri P, Lombardo G, Costanzi E, Cianetti S, Montaseri A, Marinucci L. Biological effects of resin monomers on oral cell populations: descriptive analysis of literature. Eur J Paediatr Dent. 2019 Sep;20(3):224-232. doi: 10.23804/ejpd.2019.20.03.11.

4. Line 34 The authors, noting that the definition of biocompatibility has changed in recent years, forgot to insert the new definition

5. At the end of the introduction section, the null hypotheses of the study must be inserted, which will then have to be refuted in the discussion in light of the results obtained

6. Line 47 The authors do not specify whether titanium and Cr-Co refer to the abutment or upper prosthetic reconstruction

7. Line 78 Why were these implant volumes and dimensions selected? Give a rational justification

8. Line 100 Are there works in the literature that have used the same modifications of the ISO standards mentioned, as used by the authors in this work?

9. Line 116 lack of commercial information of the spectometry

10. Line 131 ZEISS commercial information is missing

11. The authors must prepare a specific paragraph on statistical analysis

12. The graphs in Figure 1 are illegible. Replace them with histogram analysis for example

13. Figure 2 is unclear (for example the letters a, b, etc are missing on the graphs

14. The clinical implications of the results obtained, which are fundamental for the reader, are missing in the discussions

15. The English of the manuscript is of poor quality. I require a thorough and certified check by the authors in order to accept the scientific work

Author Response

Response to Reviewer 2 Comments

1. The title is misleading because anodizing is only an observed mechanism while the focus of the work is the ionic release from different implant and prosthetic solutions

The title has been revised

2. Line 12 insert “prosthetic” restoration

Inserted

3. A missing part of the introduction is that relating to the potential effects of cytotoxicity of various dental materials, a much debated topic in the scientific literature of recent years. In this regard, I suggest to insert, in the reference section and in the discussion, the following scientific work which could help the reader in understanding the problem:

Pagano S, Coniglio M, Valenti C, Negri P, Lombardo G, Costanzi E, Cianetti S, Montaseri A, Marinucci L. Biological effects of resin monomers on oral cell populations: descriptive analysis of literature. Eur J Paediatr Dent. 2019 Sep;20(3):224-232. doi: 10.23804/ejpd.2019.20.03.11.

This have been included within the Introduction.

4. Line 34 The authors, noting that the definition of biocompatibility has changed in recent years, forgot to insert the new definition

The definition and some extra reference have been included.

5. At the end of the introduction section, the null hypotheses of the study must be inserted, which will then have to be refuted in the discussion in light of the results obtained

The null hypothesis has been included at the end of the Introduction.

6. Line 47 The authors do not specify whether titanium and Cr-Co refer to the abutment or upper prosthetic reconstruction

This sentence has been revised to relate material and each prosthetic element.

7. Line 78 Why were these implant volumes and dimensions selected? Give a rational justification

They are clinically common measures and it has been included in the manuscript.

8. Line 100 Are there works in the literature that have used the same modifications of the ISO standards mentioned, as used by the authors in this work?

These standards were used by other previous studies that are included in the reference. For example: Alrabeah, G.O.; Knowles J.C.; Petridis H. The effect of platform switching on the levels of metal ion release from different implant-abutment couples. Int J Oral Sci 2016, 8, 117-125. Kassapidou, M.; Hjalmarsson, L.; Johansson, C.B.; Hammarström Johansson, P.; Morisbak, E.; Wenneberg, A.; Franke Stenport, V. Cobalt-chromium alloys fabricated with four different techniques: Ion release, toxicity of released elements and surface roughness. Dent Mater 2020, 36, e352-e363.Moreover, other included references studied several modifications of these standards; for example, Okazaki, Y.; Gotoh, E. Comparison of metal release from various metallic biomaterials in vitro. Biomaterials 2005, 26, 11-21. Yamazoe, M. Study of corrosion of combinations of titanium/Ti-6Al-4V implants and dental alloys. Dent Mater J 2010, 29, 542-553.

9. Line 116 lack of commercial information of the spectrometry

This information was provided in the next paragraph with other details about the analysis.

10. Line 131 ZEISS commercial information is missing

This have been corrected.

11. The authors must prepare a specific paragraph on statistical analysis

There is a specific paragraph at the end of the Materials and Methods section.

12. The graphs in Figure 1 are illegible. Replace them with histogram analysis for example

This Figure has been rearranged to increase its legibility.

13. Figure 2 is unclear (for example the letters a, b, etc are missing on the graphs

This Figure has been rearranged to increase its legibility.

14. The clinical implications of the results obtained, which are fundamental for the reader, are missing in the discussions

Discussion has been completed with the reviewer’s comments.

15. The English of the manuscript is of poor quality. I require a thorough and certified check by the authors in order to accept the scientific work

English has been revised throughout the manuscript.

Round 2

Reviewer 1 Report

I propose to accept reviwed manuscript in present form.

Reviewer 2 Report

all requests were added