Bone Damage during Dental Implant Insertion: A Pilot Study Combining Strain Gauge and Histologic Analysis

Round 1

Reviewer 1 Report

I have reviewed the manuscript entitled “Bone damage during dental implant insertion - a pilot study combining strain gauge and histologic analysis” for a publication in Applied Sciences as an original article. However, after careful review of this manuscript I regret to inform that I do not recommend it for publication in its current form. I have some comments to the Authors.

How many animals gave the ribs, how old and which gender animals? Were ribs from the same animal? Was the periosteum entirely removed? Did you measure cortical thicknesses of the ribs? How were ribs stored (dry?, in PhS?, cooled?, frozen?, thawed?) Storage and sample preparation can strongly influence results.

In the aim of the study, information that is a model study is required, as no examination of actual buccal bone plate were performed.

The information about the n number per implant type must be given in materials and methods section. Was sample size calculations performed before the test? What is the power test for n=5 ?

A greater number of repetitions should be performed to limit the observed variation (L214).

How was the drilling's perpendicular direction secured?

Authors state that Welch t-tests for pairwise comparisons and Pearson correlation are not very sensitive with respect to a violation of normal distribution of measurement values. Appropriate references should be given. Datasets with at least one set of  non-normal distributions should be examined using non-parametric Mann–Whitney U test.

Table 1. nomenclature . In your work, you refer to Straumann and Astra. These names should be clearly visible as implant types in Table 1

Table 2. units needed - each physical value should be given with corresponding unit. All abbreviations in the table should be explained in the table footnote.

L52-55 not clear, please rephase. Also when you refer to other studies, giving the SD value without the information about the n number (n-22 in this case) is redundant. please remove.

L100, 101 BMC – bone mineral density, BIC - bone to implant contact, and others. All abbreviation should be defined when first used.

L106 Figure 4a

L107 Figure 4b

L107 please remove. As a rule of thumb, a tendency is set for  0.1>p>0.5. P-value of 0.772 or 0.892 barely can be considered as "tendency".

Author Response

Please see the document attached

Author Response File: Author Response.pdf

Reviewer 2 Report

Although, light is put to an interesting aspect of implant dentistry, some improvements have to be done before publishing.

Introduction

1. „In an animal study comparing 41 different drill protocols, a correlation between insertion torque and radiographic bone 42 loss after 6 weeks of healing was found“

Please explain what was found.

2. Initial marginal bone loss after implant placement has been described as the result 51 of an adaptive bone response to surgical trauma and implant loading.

Not only - for example also biologic width might play a role for bone remodelling, please change accordingly.

3. As a potential solution to mechanically overloading alveolar bone during implant 56 insertion, implants with a triangular cross-section have been introduced. However, two 57 clinical studies did not identify major differences with circular cross-section neck implants 58 apart from somewhat reduced crestal bone loss.

This statement goes to discussion and has to be assessed more thoroughly.

M&M

1. Needs to be described and organized clearer: for example, nowhere is written how many implants were placed/ how many specimens were assessed.
2. „2mm to the buccal bone surface“ authors have to describe the situation different: „2mm to the cortical plate, simulation the buccal bone surface“
3. „One bucco-lingual section....“ = should be described as sagittal.
4. Statistical analysis: in my eyes, to determine if something is statistical significant, authors have to provide a power calculation based on the primary outcome measurments, defining what could be significant. Unfortunately the current paper lacks of all these aspects.
5. Again, the reader has to search the number of specimens in the abstract...
6. BIC in perecent would be an interesting outcome.

 

Discussion

1. It can be assumed that primary stability of Straumann implants relies more on cortical bone while Astra implants more strongly engage trabecular
2. Based on the results obtained this conclusion can not be taken.
3. Authors should discuss possible implications or consequences of micro and macrocracks on living vasculated bone in patients.

Author Response

Please see the document attached

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Thanks to the authors for their diligent attention to the comments made.However, all item listed in table 3 sholud be given with their corresponding physical units - BMD (g/cm2), BIC (% ?), microT (total or per bone length section?) and others. If you don't want give them in table, they can be possibly placed in table footnote.

Author Response

Thank you very much for your comment.

We have modified the table including necessary units / informaiton in the footnote of the table.

Reviewer 2 Report

Manuscript can now be published. thank you.

Author Response

Thank you very much!