Penetration Depth of Initiated and Non-Initiated Diode Lasers in Bovine Gingiva

Round 1

Reviewer 1 Report

The manuscript entitled “Penetration Depth of Initiated and Non-initiated Diode Lasers in Bovine Gingiva” by Georgios E. Romanos et al. presented an ex vivo study of the penetration depth of 445nm and 970nm diode lasers on bovine gingiva samples. The continuous wave and pulsed modes of diode laser with initiated and non-initiated tips were investigated. 

Overall, the manuscript is well-written with detailed descriptions of sample preparation steps, experimental measurements, and data analysis methods. The authors also clearly interpreted their observations based on the measured penetration depths in each case. 

However, I have some questions that need to be addressed before publication. I recommend a major revision of the manuscript for the authors to answer the following questions:

(1) On line 169, the authors claimed “The results showed that overall pulsed modes displayed less thermal damage than continuous modes. This is explained by the fact that the pulsed setting allows for thermal relaxation of the targeted tissues and therefore less thermal penetration depth.” However, when working in pulsed mode, the laser is chopped with 50% duty cycle, so the average laser power on the sample should be 1W (with 2W C.W. mode input). If I understand correctly, the authors need to measure with 4W C.W. mode input instead. In this case, we will have the same 2W average laser power on the sample for both C.W. and pulsed modes. If we still observe less thermal damage from pulsed mode, we can then claim “… the pulsed setting allows for thermal relaxation of the targeted tissues and therefore less thermal penetration depth”.

(2) For the results in Table 1, with pulsed mode, why the 970nm non-initiated penetration depth is about 1 order smaller than all other experimental groups? 

(3) I didn’t find where the authors mention Fig. 1, Fig. 2a, and Fig. 2b in the manuscript. Please add corresponding discussions in the main context or supplementary material. 

(4) I suggest the authors to add a schematic diagram of the experimental setup so that readers can understand the laser setups.

 

Author Response

Dear reviewer 1:

Thank you for your time reviewing our manuscript.  We appreciate the comments you made in your critical review.

In regard to your comment Nr. 1: You are right, the pulsed mode of 2 Watt mean power represents 1 Watt since the duty cycle is 50%. We were interested in using the power setting of 2 W (for c.w. and pulsed Mode) based on the manufacturer's recommendation and the literature to compare two different settings in the device and then illustrate the different outcomes. The intent was not to compare 1W vs. 2W since it is self-explanatory that 1W energy transfer into the tissue should be lower than 2W. However, we cannot provide data with the 4W pulsed mode power setting (50% duty cycle) at this time.

Comment Nr. 2: We have checked again our data and the statistics and there is no mistake regarding the lowest penetration depth for the 970nm non-initiated group. It is about 1 order smaller than all other experimental groups and this might be associated with the difference in Laser-tissue interactions in this experimental model.

Comment Nr. 3: There is only one figure in the manuscript (i.e. Fig. 1). We revised the submitted files.

 

Comment Nr. 4: We present now the laser settings in the text in a more clear way 

 

 

Author Response File: Author Response.jpg

Reviewer 2 Report

Manuscript No:  applsci-2076697

Title:  Penetration Depth of Initiated and Non-initiated Diode Lasers in Bovine Gingiva

 

Authors:  Georgios E. Romanos, Nathan E. Estrin, Agata Lesniewski, Steve McClain, Wei Houston

 

A. Overview

1. In this manuscript the authors report on evaluation of the penetration depth of 445 and 970nm diode lasers using both initiated and non-initiated fibers on bovine gingiva in an ex vivo model

2. The contents are expressed clearly.

3. The manuscript is well organized, however the manuscript must follow journal style

4. It is written in reasonable English.

5. The authors have acknowledged recent related research.

6. As long as my knowledge, the work presented is original.

 

 

B. Detailed analysis.

Abstract – very well written but does not agree with journal style

1. Introduction: provides an interesting approach to the subject and there are up to date references.

 

2. Materials and Methods

A more detailed illustration of the methodology is missing – use photographs and diagrams to help readers. As well photographs of the equipment sans specimens.

 

3. Results and Discussion

As before the results must be given in Tables and graphs.

 

 

C. Overall assessment

The work presented here is very interesting and has potential for further development in the field. In my opinion the manuscript can be published after Major corrections in the manuscript

 

C. Review Criteria

1. Scope of Journal

Rating: Medium

2. Novelty and Impact

Rating: Medium

3. Technical Content

Rating: Medium

4. Presentation Quality

Rating: LOW

Author Response

Dear reviewer 2: Thank you for the positive criticism in regards to our manuscript.

We considered your comments seriously and made revisions to provide clarity. We noticed that the submitted photographs were from a previous version and they created confusion for the readers and reviewers. Therefore, we submit only one photograph that combines all the histological data.

We hope now you recognize the difference in the revised manuscript and that you agree with our resubmission. The language has been improved as well.

 

Round 2

Reviewer 1 Report

The authors’ explanations to my comments seem reasonable. And the revised manuscript has addressed my questions appropriately. I would recommend its publication on Applied Sciences.