Is Complete Re-Osseointegration of an Infected Dental Implant Possible? Histologic Results of a Dog Study: A Short Communication
Round 1
Reviewer 1 Report
The authors continue to present incongruences regarding the sample used in the study
Page 1 line 43 – authors mention that the study employed 8 dogs and that for each dog 8 implants would be placed which equates to 64 possible implants. Also, according to the authors 48BL and 24 NA would be placed = 72 implants which would correspond to 9 dogs and not 8 dogs?
But in page 2 line 68 the authors say that they used 1 implant per dog as control with 2 nobel and 4 straumman which equates to 6 dogs? So for the reviewer the question remains how many dogs were used in the study ? 6? 8? 9?
Again in figure 1 (figure) the authors show a allocation ratio of 1 nobel active implant for 3 straumman bone level which corresponds to 2 NA and 6BL per dog and considering the 6 dogs mentioned as control would correspond to 12NA and 36 BL and if we consider the 8 dogs mentioned in page 1 it would equate to 16 NA and 48 BL. Regardless of the math tested by this reviewer the numbers mentioned by the author alongside the manuscript are incoherent and don’t add up.
Figure 1 (table) – again the table does not reflect the text. Mainly the authors say that 1 implant per dog was used as control so where is the control for dog 3 and dog 7? Also when the implant is considered as control it cannot be considered as treated and not treated (example in dog 4 the implant Tiunite is non treated so it is removed from the treated group but the SLA not treated are also in the treated groups equating to having dogs with 9 implants when only could have 8 (dog 1, dog2, dog 6).
Figure 4b shows 5 implants placed when the figure drawing only shows 4 implants per quadrant?
I think that the authors need to rephrase and explain better how the number of implants were obtained.
The commas need to be replaced by point in the decimals.
Figure 7 needs to have indicated the number of implants compared in each group.
Discussion still needs improvement and English proof reading.
Author Response
Please see the attached file.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Dear Authors,
the manuscript is interesting and adequate for the topic treated but some information need to be added:
introduction: please indicate the meaning of Classical Cleaning with a reference. check figure 1, diameter of the osteotomy differ from implant size results: please check the number of implant in the SLA EC group results: please show in the histology figures both types of implant in each EC and CC groups discussion: please indicate based on previous studies, also preclinical, why the CC group, from your point of view, had worse results (no complete osseointegration in none of the cases) compare to ECAuthor Response
Please see the attached file.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Still minor changes are needed:
1- English proofreading needs to be adressed since some gramatical errors were found
2- Replace the commas by dots in the decimals (example figure 1; page 1 and page 2 - 0,9%)
3- Page 2, line 73 - please correct "One implant per dog (2 Nobel, 4 Straumann)" by One implant per dog (2 Nobel, 6 Straumann)
4- Page 5, line 89 - please correct ( xx Tiunite implants and xx SLA implants were treated in the EC group and xx Tiunite implants and xx SLA implants were treated in the CC group)
5- Page 5, line 98 - please correct GC for CC
6- Page 6 - please correct Figure 1 for Table 1
Author Response
Answer to the reviewer
introduction: please indicate the meaning of Classical Cleaning with a reference.
Answer:
To clarify this, we added following sentence:
This approach was chosen in reference to previous studies [5].
check figure 1, diameter of the osteotomy differ from implant size
Done
results: please check the number of implant in the SLA EC group results
Checked again and found no mistake. Please advice.
please show in the histology figures both types of implant in each EC and CC groups discussion
Done.
We added the following text:
The latter was proven through histology (Figure 5-8). Re-osseointegration is defined as new bone in direct contact to the formerly infected implant surface. Soft tissue thickness correlates to bone level (9). Thus a bone regeneration to the platform cannot be expected in case of exposure when the shoulder of the implant was visible. Complete regeneration if chewing forces were applied to the implant can also not expected even of the site stayed covered. Interestingly a complete regeneration was only possible in EC group – even under this circumstances.
please indicate based on previous studies, also preclinical, why the CC group, from your point of view, had worse results (no complete osseointegration in none of the cases) compare to EC
Done
We changed the text in Discussion:
To the best knowledge of the authors a complete regeneration was never described in the literature before. This paper does not investigate the reasons for this observation. In context of previous literature it can be assumed that EC in contrast to CC removes the bacterial biofilm and other remnants to an extent that complete reosseointegration was possible [6,7].
Author Response File: Author Response.docx
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
Dear Editor,
Regarding the submitted manuscript “ Is complete re osseointegration of an infected dental implant possible – histological results of a dog study. A short communication ” the presented study is intended to be an short communication of an animal study to assess the properties of a cleaning protocol in peri-implantitis treatment.
Overall appreciation
I think the authors should address some corrections/clarifications before it is considered for publication
In the material and methods section the authors should state: electrolytic cleaning needs to be better described (describe the application method, time of application, etc) Explain how the number of animals was arrived at. Provide details of any sample size calculation used. (Item 10b of ARRIVE Guidelines) If you have 6 dogs (page 2 the author mention that the negative control was 1 implant per dog equating to 6) can you provide further details regarding the number of placed implants per brand in each dog? According to figure 1 the allocation ratio is 1 nobel implant per 3 straumman, while the authors mention a 1:2 ratio in the final sample (24 tiunite for 47 straumman). The authors state that 4 implants per quadrant in the mandible (page 1) being that it equates to 8 implants per dog, and if you take into consideration that there are 6 dogs (page 2) the total number of implants would be 48 but the authors mention 71 placed implants? The authors mention that the two types of treatment were randomly assigned (CC and EC), but that randomization method needs to be described and the total number of implants (per brand) in each group need to be mentioned. When looking at the results several considerations: According to what the authors state, the evaluated bone gain was only evaluated in 17 samples because they were the only that were covered? That corresponds to 54 samples without bone gain independent of proposed method (almost 70%)? Of the 17 covered samples how many were of each brand? Being that they present different implant surfaces decontamination can be influenced by the implant surface. “No complete re- osseointegration could be proved for Implants treated with CC but for some of the implants treated with EC (Fig. 4 and 5)” – How many? Please provide information Decimals should be with a point and not a comma Figure 6 – Authors should be careful when stating that the bone gain was higher in one group since from what I see in the picture there aren’t statistical differences. And with the provided data there aren’t differences between methods. With the defects merging between sites the results directly correlate with inter influence
Discussion: Interpret the results, taking into account the study objectives and hypotheses, current theory and other relevant studies in the literature. Comment on the study limitations including any potential sources of bias, any limitations of the animal model, and the imprecision associated with the results. Describe any implications of your experimental methods or findings for the replacement, refinement or reduction (the 3Rs) of the use of animals in research.
From the expressed results I do not see major differences between the two techniques, thus I can only consider it as a proof-of principle of a non-inferiority trial, but the numbers do not add up nor the results are clearly stated thus needing reformulation.
Based on the manuscript analysis I believe that the manuscript can be considered for publication after the proposed corrections.
Reviewer 2 Report
Authors conduced this animal study with the goal of demonstrating re-osseointegration of dental implant after applying a new cleaning protocol.
Study has serious flaws and many unanswered questions.
In the introduction, authors report pilot series device.. not sure what that means? IRB (Animal approval) was obtained in Brazil for this study submitted from Europe that raises concern. Authors reported 'augmented area' multiple times. Was bone grafting performed or just the membrane alone was used..? Authors reported using alizarin red staining but no results from it were presented. Authors reported using a negative control but no results from this group was included. How was bone gain measured? Methodology in general, lacks the required details. No mention of statistical analysis in methodology. Better to include the surgical photos (with membrane in place) as a composite image in figure 3.