Bone Loss in Implants Placed at Subcrestal and Crestal Level: A Systematic Review and Meta-Analysis

Round  1

Reviewer 1 Report

Taking into account all the several features, the accuracy, scientific quality, scientific content and the interpretation of the results are very good.

- The approach is interesting and the topic is appropriate for the journal.

-        The work  has a very clear structure and all the sections are well written in a way that is easy to read and understand. In addition, the structure of the paper is very good.

-        “Table 2a & 2b” should be replaced by “Tables 2a and 2b”. The authors should check it.

-        It seems that the paper does not contain repetitions.

-        The quality of some figures should be improved.

-        The title is adequate and appropriate for the content of the article.

-        The abstract contains information of the article.

-        Figures and captions are essential and clearly reported.   

Author Response

Response to the reviewer's comments in Word file: Reviewer 1

Author Response File: Author Response.pdf

Reviewer 2 Report

The present study analyses the effect of crystal v/s subcrestal placement of implants on bone loss and other soft tissue parameters. The study has been well designed and written. I have a few concerns as mentioned below:

The first concern with the study is the lack of inclusion/exclusion criteria for the  follow-up period. Two of the included studies have follow-ups of 1-2 and 3 months, respectively. It would be good to include studies with a follow-up period of at least 6 months, preferable 12 months, post loading. The authors have done well by not including these studies in the meta-analyses, but it would be good to have strict inclusion criteria in regards to the follow-up period for the benefit of the readers.

The second concern is regarding the meta-analysis for non-RCT studies. You have included 2 studies, one having implants with ext connection and the other with both ext and int connection. In my opinion, it is something which, ideally, should not be compared. It would be a good idea to not include this analysis in the article.

It would be good to see the effect of immediate v/s delayed loading separately to find if the timing of loading has an effect on the bone loss in both groups.  

Some other minor modifications are listed below:

Abstract

Pg 1 lines 15,16 - Please mention both the start and end period of the literature search.

Pg 1 line 21 - Please avoid starting a sentence with a numeral eg. replace "3" with "Three". Please make sure to make modifications like this in the entire manuscript.

Pg 1 line 24 - Avoid using the word "similar" unless the values are exactly, numerically, similar. You could rephrase it as "comparable" or you could rephrase the whole sentence.

Introduction

Pg 1 lines 43,44 - "Thus, with the...achieving secondary stability". Please rephrase the sentence in a grammatically correct way or join it with the previous sentence. 

Pg 2 line 74 - Incomplete sentence.

Results 

Pg 6 line 173 - "With respect to the moment of implant placement", please replace 'moment' with 'timing'.

Pg 12 line 189 - Replace 'RTC' with 'RCT'.

Author Response

Response to the reviewer's comments in Word file: Reviewer 2

Author Response File: Author Response.pdf

Reviewer 3 Report

Authors shold improve the English grammar

Author Response

Response to the reviewer's comments in Word file: Reviewer 3

Author Response File: Author Response.pdf