Xeno-Hybrid Composite Scaffold Manufactured with CAD/CAM Technology for Horizontal Bone-Augmentation in Edentulous Atrophic Maxilla: A Short Communication

Round 1

Reviewer 1 Report

Please see the attached review document.

Comments for author File: Comments.pdf

Author Response

Response to Reviewer #1 Comments

Major suggestion 1: - The motivation and improvement of the new horizontal bone augmentation in edentulous atrophic maxilla in comparison to traditional technology is not presented properly. For instance, why this new procedure is beneficial to use? Cone-beam computed tomography (CBCT) and CAD / CAM combined technologies makes it possible to directly customize biocompatible scaffold. This technique has been already shown into effect in previous references 8 and 9. Is this the first time for "horizontal bone augmentation"? Sequential reasoning of the novelty of this proposed technique is required.

Response: The section "Introduction" has been wholly rephrased to describe risks and benefits of traditional bone augmentation procedures and the advantages of the new protocol in the reconstruction of the edentulous atrophic maxilla.

Major suggestion 2:   The paragraph starting in line 296 is a very useful paragraph which appears to be a good fit for motivation of the study. Can this be placed at the beginning of the manuscript?

Response: As suggested, the paragraph starting in line 296 was placed in the section “Introduction”.

Major suggestion 3: What does 3D-TC represent in line 97? Three-dimensional tissue culture or something else? Can this be clarified?

Response: The expression three-dimensional imaging acquisition with computed tomography (3D-CT) has been corrected.

Major suggestion 4: A description of the patient's dental problem is needed for the section “surgical and prosthetic procedure”.

Response: As suggested, the description of the patient's dental problem was added in the section “materials and methods”.

Major suggestion 5: In line 142, any references for the reconstructive surgery procedure would be better and the choice of this procedure would encourage the reader to follow the detailed procedure in reference.

Response: As suggested, the description of the reconstructive surgery procedure was implemented.

Major suggestion 6: Is there any long term age benefit of using the custom-made bone block for this reconstructive surgery? Although a 2 year follow-up CBCT is shown in figure 9 is there any reference of long-term age effect (~10 years) of the bovine-derived xeno-hybrid composite?

Response: To the best of the authors’ knowledge, no papers are present in the literature reporting the use of xeno-hybrid composite scaffold manufactured with CAD/CAM technology in horizontal bone-augmentation of edentulous atrophic maxilla. There are present case reports and case series only related to small bone defects or craniofacial bone reconstruction.

Minor Suggestion 7: Can a scale bar be added to figure 6, 7 and 8 showing the histological analysis?

Response: As suggested, the scale bar has been inserted in each figure.

Minor Suggestion 8: In line 212, should it be 'where large marrow spaces are present'?

Response: Marrow spaces were between the trabeculae. They represented about 25% of the bone structure.

Reviewer 2 Report

Xeno-hybrid composite scaffolds manufactured with cad/cam technology for horizontal bone augmentation in edentulous atrophic maxilla: a short communication

Summary:

The study showed a new protocol for reconstruction of the horizontal severely resorbed edentulous maxilla. In this work they have utilized 3D imaging of the patient using cone-beam computed tomography (CBCT) to diagnose and CAD/CAM technique to fabricate the graft blocks and finally they have performed the surgery and analyzed the applicability of the technique for rehabilitation via implant-supported prostheses. They have analyzed the integration between the graft and the recipient site, histological analysis to check the newly formed bone as well as presence of osteocytes lacunae. They have also checked the occurance of any inflammation or bone resorption after 2 years via CBCT.

Minor issues; Introduction:

The authors have provided enough information for importance of the work. However, it could have been better if there were more references for each of the reconstruction techniques named for supporting the information. For examples, for ridge splitting and block grafts, there are only 2 references named.

For line 79-80, references need to be provided. For autologous bone harvesting or using homologous, heterologous or alloplastic grafts, there is not enough references to support the sentences and the one provided is a review paper but from 2016.

References for CBCT/CAD/CAM techniques are not new, 2014, 2016.

I think there should be more information in the introduction section on how their technique would fill the gaps in the current technology used for reconstruction of edentulous maxilla. And what advantage it brings over the current fabrication techniques. Although more reasonings have provided in the abstract and discussion part.

In total, introduction needs more literature review for current techniques and to support the need for their protocol.

There is no clear hypothesis for the project, except that the proposed protocol will provide advantages over the other techniques in regards to reducing the number of needed surgeries, shortening the operating times because the manual shaping of the blocks and adaptation at the recipient sites are not necessary.

Major issues; Results, Discussion and conclusion

I am not sure if it is possible to have control for these experiments, but currently there is no control for the samples analyzed in the experiments.

The data obtained show the applicability of the current protocol, however, whether this protocol is better to the current protocols, have not been supported by the data. The need for less surgeries and less time to make the samples are understandable, but they are not something to conclude from the data provided. So I think the results do not support the hypothesis.

Also It could have been better if there were some information about the limitations of the study and areas for future work.

Author Response

Response to Reviewer #2 Comments

Minor issues; Introduction

 The authors have provided enough information for importance of the work. However, it could have been better if there were more references for each of the reconstruction techniques named for supporting the information. For example, for ridge splitting and block grafts, there are only 2 references named.

For line 79-80, references need to be provided. For autologous bone harvesting or using homologous, heterologous or alloplastic grafts, there is not enough references to support the sentences and the one provided is a review paper but from 2016.

References for CBCT/CAD/CAM techniques are not new, 2014, 2016.

I think there should be more information in the introduction section on how their technique would fill the gaps in the current technology used for reconstruction of edentulous maxilla. And what advantage it brings over the current fabrication techniques. Although more reasonings have provided in the abstract and discussion part.

In total, introduction needs more literature review for current techniques and to support the need for their protocol.

Response: The "Introduction" section has been wholly rephrased to describe the risks and benefits of traditional bone augmentation procedures and the advantages of the new protocol in the reconstruction of the edentulous atrophic maxilla.

More new references have been added related to augmentation procedures, autologous bone and biomaterials, and CBCT/CAD/CAM technologies.

There is no clear hypothesis for the project, except that the proposed protocol will provide advantages over the other techniques in regards to reducing the number of needed surgeries, shortening the operating times because the manual shaping of the blocks and adaptation at the recipient sites are not necessary.

Response: The present short communication aimed to describe a new protocol, used by authors in the reconstruction of the horizontal severely resorbed edentulous maxilla, as a potential alternative to conventional techniques.

Major issues; Results, Discussion and conclusion

I am not sure if it is possible to have control for these experiments, but currently, there is no control for the samples analyzed in the experiments.

The data obtained show the applicability of the current protocol, however, whether this protocol is better to the current protocols, have not been supported by the data. The need for less surgeries and less time to make the samples are understandable, but they are not something to conclude from the data provided. SoI think the results do not support the hypothesis. Also, It could have been better if there were some information about the

limitations of the study and areas for future work.

Response: Discussion and conclusions were rephrased and implemented to highlight the advantages of the proposed approach compared to traditional augmentation procedures. In the authors' mind, the aim of the present paper was not to report an experiment, which requires controls, hypotheses and supporting results, but their experience in the treatment of selected clinical cases. Therefore, given information does not have to demonstrate the superiority of the described strategy related to current procedures but offers clinicians a potential alternative.

As suggested, the limitations of the study and the need for future controlled studies and long-term follow-ups were added.

Round 2

Reviewer 2 Report

The authors have adequately addressed the concerns.

Author Response

All the reviewer's concerns have been adequately addressed.