Chin Morphology in Relation to the Skeletal Pattern, Age, Gender, and Ethnicity

Round 1

Reviewer 1 Report

1. In abstract: Results part incomplete. Should add numerical results and p values.

2. Power sample size part is missing. Should add.

3. Korean sample size are not uniform. Should match.

4. Table 1 presents the mixed sample. Should separate.

5. Calibration, reliability, and validity part is missing. Repetition of the measurements part is essential.

6. Results: Numerical data should be present.

7. Age grouping missing.

8. Details table of the age-related results is missing.

9. Discussions: Some important results-related discussions are missing.

10. Conclusion should be based on objectives.

11. Below reference can be used -

https://pubmed.ncbi.nlm.nih.gov/32015645/

Author Response

We appreciate the reviewer’s encouraging words and careful consideration of our amended article. Each of the issues pointed out by the reviewers has been addressed, and the manuscript has been modified accordingly.

Reviewer 1 comments
1. In abstract: Results part incomplete. Should add numerical results and p values.

Thank you for bringing this up. We have added the p values to the results part. Due to character restrictions, the numerical values have been updated in the results section of the main text. We trust you can comprehend.

2. Power sample size part is missing. Should add.

Thank you for pointing this out. Utilizing already-available resources, this investigation was carried out as an exploratory study. Consequently, it was done without deciding on the sample size. The Materials and Methods part’s pages 2 and 3 have descriptions of this topic on lines 95 and 96, respectively.

3. Korean sample size are not uniform. Should match.
Thank you for making this observation. Additional samples cannot be added since this research employs already-existing materials. In the discussion section (page 8 lines 285–287, and page 9 lines 300–302), the non-uniform sample size was cited as a restriction that will affect subsequent research.

4. Table 1 presents the mixed sample. Should separate.

Thank you for your advice. To distinguish each sample, we amended Table 1.

5. Calibration, reliability, and validity part is missing. Repetition of the measurements part is essential.

Thank you very much for your suggestion. On page 3, lines 127–136, we made corrections to the measurement technique and its dependability.

6. Results: Numerical data should be present.

Thank you for making this observation. The numerical results and p values have been added to the results section.

7. Age grouping missing.
Thank you for pointing this out. We have included it in the revised Table 1.

8. Details table of the age-related results is missing.
Thank you for making this observation. On page 6, lines 212–213, we have inserted the age findings

9. Discussions: Some important results-related discussions are missing.

Thank you for your suggestion. We have revised the discussion part.

10. Conclusion should be based on objectives.
Thank you for your advice. Corrected the conclusion part.

11. Below reference can be used
https://pubmed.ncbi.nlm.nih.gov/32015645/

Thank you for the guidance. It has served as a guide for us.

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript is about chin morphology and comparisons between the Koreans and Egyptians ethnic.

Page 3: The DICOM data of CBCT images from both Korean and Egyptian patients were processed using the same Invivo 6 software? Who conducted the analysis? Same person or different person?

Page 3, line 116:  A volumetric assessment (mm3) 116 of the chin was performed using the Invivo 6 automatic function after calibration using 117 an aluminum bar, as described in a previous study by Katayama et al (2014). Katayama used Analyzed image processing software to segment the mandible using threshold method. This study used Invivo 6 software which is different from Analyze. Please elaborate the volumetric assessment process using Invivo 6.

Page 4: Statistical analysis. Did the authors perform the reliability test? Could be human errors during measurements. Any intra-rater and inter-rater analysis?

Page 4: Figure 2 shows the definition of chin. How did the authors measure the chin volume? Maybe add one figure explaining the volume assessment method.

Page 5, Table 2: The chin volume for Korean is 3668.19 (1297.25) mm3 and the Egyptian is 2838.46 (856.26) mm3. However, the study by Katayama et al (2014) where the authors referred in this manuscript, the mandibular volume for 118 Japanese adults is 63235.2 (10169.6) mm3 which is very much different from their results. Please explain.

Author Response

We thank the Reviewer for providing a thorough review of our manuscript, and for the valuable suggested changes. We have responded to each item in the Reviewer’s critique and have modified the manuscript accordingly.

Reviewer 2:

The manuscript is about chin morphology and comparisons between the Koreans and Egyptians ethnic.

We thank the Reviewer for the thorough review of our manuscript.

Page 3: The DICOM data of CBCT images from both Korean and Egyptian patients were processed using the same Invivo 6 software? Who conducted the analysis? Same person or different person?

Thank you for pointing this out. All DICOM data analyzes were performed using Invivo™ 6 software, and the analysis was performed by the same operator. The text on page 3, line 111 has been corrected as follows: "Data analysis was performed by a single operator. all DICOM data were imported into Invivo™ 6 (Anatomage, San Jose, CA, USA) for further processing and analysis."

Page 3, line 116: A volumetric assessment (mm3) 116 of the chin was performed using the Invivo 6 automatic function after calibration using 117 an aluminum bar, as described in a previous study by Katayama et al (2014). Katayama used Analyzed image processing software to segment the mandible using threshold method. This study used Invivo 6 software which is different from Analyze. Please elaborate the volumetric assessment process using Invivo 6.

Thank you for pointing this out. The process for the volume evaluation using Invivo™ 6 was unclear, so we have described the measurement on page 3, line 125. We have also added Figure 3 for more information on the process.

Page 4: Statistical analysis. Did the authors perform the reliability test? Could be human errors during measurements. Any intra-rater and inter-rater analysis?

Thank you for pointing this out. The reliability was confirmed using the Dahlberg formula.

The following sentence was added to page 4, line 132: "To determine possible operator error, 30 CBCT images were randomly selected and measured at 2-week intervals under the same conditions using Dahlberg’s formula."

We have also added the following reference: "Springate, S.D. The effect of sample size and bias on the reliability of estimates of error: a comparative study of Dahlberg's formula. Eur J Orthod. 2012, 34, 158-163."

Page 4: Figure 2 shows the definition of chin. How did the authors measure the chin volume? Maybe add one figure explaining the volume assessment method.

Thank you for pointing this out. The process for the volume evaluation using Invivo™ 6 was unclear, so we have described the measurement on page 3, line 125. We have also added Figure 3 for more information on the process.

Page 5, Table 2: The chin volume for Korean is 3668.19 (1297.25) mm3 and the Egyptian is 2838.46 (856.26) mm3. However, the study by Katayama et al (2014) where the authors referred in this manuscript, the mandibular volume for 118 Japanese adults is 63235.2 (10169.6) mm3 which is very much different from their results. Please explain.

Thank you for pointing this out. In the study by Katayama et al., the total volume of the mandible was measured. On the other hand, in our study, we measured the volume of the chin, which is a part of the mandible. The difference in the results is considered to be due to the difference in the measurement site

Reviewer 3 Report

Comments for author File: Comments.pdf

Author Response

We thank the Reviewer for providing a thorough review of our manuscript, and for the valuable suggested changes. We have responded to each item in the Reviewer’s critique and have modified the manuscript accordingly.

Reviewer 3：

1. Overall: - the study has been conducted fairly, but the data analysis and results are unsatisfactory; discussion part failed to show the importance/ implications of the study

Thank you for pointing that out. We have revised the entire manuscript to provide more useful information to the readers.

2. Abstract:

The larger the vertical skeletal pattern, the larger the chin volume and the smaller the

width. -> perhaps replaced ‘larger’ with ‘longer’ will be easier to be understood

Thank you for pointing this out. In this study, width was the only factor that showed a statistically significant relationship between vertical skeletal pattern and liner measurement. On the other hand, volume is predominantly associated with vertical skeletal pattern, which is why we used the word "larger." Furthermore, the use of the word “longer” to describe a volume is nonsensical.

Please add on the p value for the result part in the abstract

Thank you for pointing this out. We have added the p-value for each result.

3. Introduction

Lack of information/elaboration on the clinical importance of this study of chin

morphology.

No data on previous study on chin morphology being presented.

Thank you for your suggestion. We have made additional corrections regarding the clinical importance and the previous study on chin morphology as per your suggestion.

4. Methodology

Fig 1 a: FH plane should be shown from lateral view

Thank you for your suggestion. We have changed the image of the Frankfort horizontal plane to a lateral view.

Fig 1.b. : This is not mandibular plane angle

Thank you for your comment. Fig. 1b was not meant to illustrate the mandibular plane "angle." Instead, it was meant as an illustration of the mandibular plane. Thank you for your understanding.

The reason for CBCT in the subjects needs to be mentioned/ listed

Thank you for pointing this out. We only performed CBCT scans that were necessary for treatment. We have clarified the description on page 2, line 93 as follows: “We note that the CBCT images were taken for therapeutic purposes and not specifically for this study.”

5. Results

P value need to be added in Table 2

Thank you for your suggestion. We have added the p-values for all marks in Table 2. All types of marks had a p<0.01.

Table 3,4,5 are confusing

Thank you very much for your comment. We have revised the tables for clarity.

6. Discussion: No clinical implications noted

Thank you for your suggestion. We have added a discussion on the clinical importance of our study on page 8, lines 260–268 as follows: “The addition of genioplasty, a surgical vertical or horizontal shift of the chin, to orthognathic surgery of the mandible leads to a more harmonious facial soft tissue morphology and a higher degree of satisfaction with the result than mandibular advancement alone [33]. On the other hand, changes in the position of the chin may result in bad joints and unexpected soft tissue changes [34]. This study shows the relationship between skeletal pattern and morphology of the chin. Three-dimensional evaluations of the chin may be helpful in treatment planning when modifying the position and morphology of the chin in orthognathic surgery, such as the direction of the slide, osteotomy line, and the amount of bone grinding.”

7. Conclusions: too long, repeating everything in the result

Thank you for pointing this out. We have revised the conclusion to be more concise on page 8, lines 292–295 as follows: “Except age, chin morphology was significantly associated with all other parameters such as ethnicity, sex, anteroposterior skeletal pattern, and vertical skeletal pattern. Evaluations chin morphology characteristics not only by linear analysis but also by volume analysis may be helpful for treatment goals in orthognathic surgery.”

Reviewer 4 Report

The paper entitled “Chin Morphology in Relation to the Skeletal Pattern, Age, Gen- 2 der, and Ethnicity” is a contribute that  aims to investigate the relationship between chin size and volume and vertical and anteroposterior skeletal patterns,  gender, ethnicity, and age. The work  provides interesting data and could be considered of interest for the readers. However before it could be considered valid for publication requires some corrections.

 

INTRODUCTION

Overall well structured, it provides all the information necessary to understand the scientific background, the knowledge gap and the objectives of the study.

MATERIAL AND METHODS

The scientific methodology used were described in a clear and exhaustive manner. About chin morphology evaluation there is only a reference to a previous study of Katayama et al [24] . It would be better to  give a description of the measurement technique used and insert some images of the methodology used. The statistical analysis used to evaluate the results is correct.

RESULTS AND

The results are described in a precise and detailed manner; graphical representation is well executed and allows a faster understanding of the results achieved in the study.

DISCUSSION

The discussion of the results is on the whole well articulated ; clinical relevance of the results should be emphasized more.

CONCLUSION

Conclusions are limited to a synthetic summary of the results obtained; this section must be revised and report preferably with a bulleted list, only the key results of the study.

Author Response

              We thank the Reviewer for providing a thorough review of our manuscript, and for the valuable suggested changes. We have responded to each item in the Reviewer’s critique and have modified the manuscript accordingly.

 

Reviewer 4：

 

INTRODUCTION

 

Overall well structured, it provides all the information necessary to understand the scientific background, the knowledge gap and the objectives of the study.

 

We thank the Reviewer for the encouraging comments and for the thorough review of our manuscript.

 

MATERIAL AND METHODS

 

The scientific methodology used were described in a clear and exhaustive manner. About chin morphology evaluation there is only a reference to a previous study of Katayama et al [24] . It would be better to give a description of the measurement technique used and insert some images of the methodology used. The statistical analysis used to evaluate the results is correct.

 

We thank the Reviewer for the encouraging comments. The process for the chin volume evaluation using Invivo™ 6 was unclear, so we have described the measurement on page 3, line 125. We have also added Figure 3 for more information on the process.

 

RESULTS AND

 

The results are described in a precise and detailed manner; graphical representation is well executed and allows a faster understanding of the results achieved in the study.

 

We thank the Reviewer for the encouraging comments and for the thorough review of our manuscript.

 

 

DISCUSSION

 

The discussion of the results is on the whole well articulated; clinical relevance of the results should be emphasized more.

 

Thank you for your suggestion. We have added a discussion on the clinical importance of our study on page 8, lines 260–268 as follows: “The addition of genioplasty, a surgical vertical or horizontal shift of the chin, to orthognathic surgery of the mandible leads to a more harmonious facial soft tissue morphology and a higher degree of satisfaction with the result than mandibular advancement alone [33]. On the other hand, changes in the position of the chin may result in bad joints and unexpected soft tissue changes [34]. This study shows the relationship between skeletal pattern and morphology of the chin. Three-dimensional evaluations of the chin may be helpful in treatment planning when modifying the position and morphology of the chin in orthognathic surgery, such as the direction of the slide, osteotomy line, and the amount of bone grinding.”

 

CONCLUSION

 

Conclusions are limited to a synthetic summary of the results obtained; this section must be revised and report preferably with a bulleted list, only the key results of the study.

 

Thank you for pointing this out. We have revised the conclusion to be more concise on page 8, lines 292–295 as follows: “Except age, chin morphology was significantly associated with all other parameters such as ethnicity, sex, anteroposterior skeletal pattern, and vertical skeletal pattern. Evaluations chin morphology characteristics not only by linear analysis but also by volume analysis may be helpful for treatment goals in orthognathic surgery.”

Round 2

Reviewer 3 Report

The manuscript improved after the revision. However,

1.     Introduction

a.     No data on previous study on chin morphology being presented in the introduction making the reader unable to correlate with other studies.

2.     Results

a.     P values have been added to Table 2. However, there are too many symbols used and is very confusing. Either standardize the symbol if all are P<0.01. Or directly spell out the value of p-value in the table (preferably)

b.     Table 3,4,5 : please add in a brief interpretation for these Tables in result/ discussion part by referring to the table 3,4,5 each.

Comments for author File: Comments.docx

Author Response

We thank the Reviewer for the encouraging comments and for the thorough review of our revised manuscript. We have responded to each of the Reviewer’s concerns and have modified the manuscript accordingly.

 

1. Introduction
2. No data on previous study on chin morphology being presented in the introduction making the reader unable to correlate with other studies.

 

Thank you for your suggestion. We have added information from previous studies regarding chin morphology on page 2, lines 56–60.

 

 

2. Results
3. P values have been added to Table 2. However, there are too many symbols used and is very confusing. Either standardize the symbol if all are P<0.01. Or directly spell out the value of p-value in the table (preferably)

 

Thank you for pointing this out. Each mark implies a comparison between different factors. When we attempted to describe them with the same mark, it became necessary to separate several tables for each factor. Therefore, we chose to use numerous marks to indicate significant differences between various factors in a single table.

We appreciate your understanding in this matter.

 

 

1. Table 3,4,5 : please add in a brief interpretation for these Tables in result/ discussion part by referring to the table 3,4,5 each.

 

Thank you for pointing this out. We have added the interpretation for Tables 3, 4, and 5 to page 7, lines 236-237, page 7, lines 246-249, and page 8, lines 277-278 of the Discussion section, and have referred to the respective tables.

Author Response File: Author Response.pdf