Bioactive Surface of Zirconia Implant Prepared by Nano-Hydroxyapatite and Type I Collagen

Round 1

Reviewer 1 Report

The authors well introduce HA and collagen to zirconia surface and do series testing to evaluated the biological activity.  There are some comments for the articles:

1.     In Fig. 7, The author uses SEM to show the morphogen of different Zr2O2, but it is not easy to confirm the HA/collagen only by SEM, suggest to further confirm the composition to use EDS spectrum analysis.

2.     In Fig.10, ALP is an early maker for osteoblast differentiation, which is normally can be observed on day 7, 14day. while the author show ALP expressed only on day 21, suggest to measure the ALP expression on the period that 7-14d and do additional quantitate testing of ALP.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

The work “Bioactive Surface of Zirconia Implant Prepared by Nanohydroxyapatite and Type I collagen” by Hun Kim, Yang Ho Lee, Nam Kwon Kim and Inn Kyu Kang is aimed to increase the bioactivity of zirconia and ensure safety in the body, by adding to the surfaces nHA and type I collagen.

However, I have some issues for the authors to address:

-After the immobilization of these substances on the zirconia, how sterile they remain? Can they be sterilized, for example, by UV treatment?

-Can you quantify the density of the particulates found in the Figure 7?

-Did the authors use the whole disks and screws to perform the experiments? Or they were cut into small pieces?

-The authors mentioned in the Discussion section about the adherence and the spread of the cells. From what I see in the SEM images, the obtained surfaces are not that smooth, and, from my knowledge, a surface topography and roughness can influence osteoblastic adherence and spread. Can the authors deliver some results and/comments on this matter?

-This paper is well organized and discussed. The experimental design is correct and results are clearly presented. The research design is appropriate and the conclusions are supported by the presented results. Overall, the paper is well organized and well written and could therefore be accepted for publication. 

Author Response

"Please see the attachment"

Author Response File: Author Response.pdf