Evaluation of Deviations between Computer-Planned Implant Position and In Vivo Placement through 3D-Printed Guide: A CBCT Scan Analysis on Implant Inserted in Esthetic Area
Round 1
Reviewer 1 Report
The article is well written and can be accepted in current form, anyway it does not add any information to the current literature.
Author Response
Thank you for your appreciation. Following your suggestion, we tried to emphasize the novelty of the study in the introduction and in the discussion and you can find the changes highlighted in the revised manuscript. Our study was conducted with the aim to assess the numeric deviation between computer planned implant position (ideal target position) and in-vivo placement (real placement position) and we hope to have contributed to increasing knowledge in this field.
Reviewer 2 Report
Dear Authors,
The work is done in a scientific way and really appreciatable. However, I have few suggestion
- Restructure the introduction to provide an insight into the story.
- Please improve the Figure 1.
- write down at least one and half page of discussion.
Author Response
Dear Authors,
The work is done in a scientific way and really appreciatable. However, I have few suggestion
- Restructure the introduction to provide an insight into the story.
- Please improve the Figure 1.
- Write down at least one and half page of discussion.
_______________________________________________________________________
Thank you for your comments.
- We restructured the introduction according to your suggestions pointing out the different types of implant insertion timing described in the literature.
- We tried to improve Figure 1 and we added other figures.
- We expanded the discussion.
Reviewer 3 Report
Please correct CTCT to CBCT in Results.
Further explanation of the reasons for the division into the two groups and the difference in results between the two groups is needed.
If you add more figures, the reader will understand better.
Author Response
Please correct CTCT to CBCT in Results.
Thank you for your comment and for noting our typing error.
Further explanation of the reasons for the division into the two groups and the difference in results between the two groups is needed.
Thank you for the comment. We tried to improve the introduction to better explain the division in two groups and added a new paragraph in the results section with the statistical analysis of the differences between the groups.
“There are also different protocols in the literature concerning the timing of implant insertion. Immediate (or post-extractive) implants are defined as those placed in a fresh extraction socket just after tooth extraction, immediate-delayed implants are those placed in an extraction socket within 8 weeks after tooth extraction, and delayed implants are any implants placed at least 2 months after tooth extraction [19]. Previous studies showed that there is no difference between these in terms of success rate and complications, while the best aesthetic result was obtained with post-extractive implants [20,21]. However, there are no studies that assess the accuracy of implant insertion with the computer-guided technique by comparing immediate and delayed protocol.”
If you add more figures, the reader will understand better.
Thank you for the suggestions. We added two more figures.
Reviewer 4 Report
This manuscript ID. applsci-1678384 titled “Evaluation of deviations between computer planned implant position and in vivo placement through 3D-printed guide: a CBCT scan analysis on implant inserted in esthetic area” was well-written. However, some specific points needed to be clarified.
Specific:
- Please add a citation to lines 50~52 “In fact, for bone thickness> 1mm the success…(4-8 weeks after extraction) are higher.
- It would be better to have been approved by the institutional review board or ethics committee.
- The implant depth was not evaluated in this study. This is the limitation of this study.
- Line182, please clarify the abbreviation VAS.
- The conclusion: [to predictable and precise] need more scientific data (implant depth) in this digital -3D printing method.
Author Response
This manuscript ID. applsci-1678384 titled “Evaluation of deviations between computer planned implant position and in vivo placement through 3D-printed guide: a CBCT scan analysis on implant inserted in esthetic area” was well-written. However, some specific points needed to be clarified.
Specific:
Please add a citation to lines 50~52 “In fact, for bone thickness> 1mm the success…(4-8 weeks after extraction) are higher.
Thank you for the comment. We added a citation.
It would be better to have been approved by the institutional review board or ethics committee.
We did not ask for an ethics committee in this study, because it is a retrospective study on CBCT. The patients had already been treated and were retrospectively included in the groups, all data were analyzed anonymously.
The implant depth was not evaluated in this study. This is the limitation of this study.
Thank you for the comment. The mean deviation of the implant axis expressed in degrees is a parameter that depends on both the vestibulo-palatal inclination of the implant and the apico-coronal depth. The angle will therefore change in relation to these two parameters. For example, if the implant depth increases, i.e. if there is a discrepancy with the pre-operative digital planning (reference position), at the same inclination, the angle decreases. We tried to clarify this in the material and methods section.
Line182, please clarify the abbreviation VAS.
We clarified the acronym in the text and thank you for noting our mistake.
The conclusion: [to predictable and precise] need more scientific data (implant depth) in this digital -3D printing method.
Thank you for your comment. We modified the conclusion in:
“The results of our study showed that there were minimal and non-clinically relevant differences between preoperative virtual planning and postoperative implant positioning assessed on CBCT and that there were no significant differences between immediate and delayed placement.”
Reviewer 5 Report
Introduction:
Please emphazise more on the intention to compare both groups. Why is it relevant? This has not been expressed sufficiently
Discussion:
The aim of the study is not clear. Authors state that it should reveal differences between präoperative planning and postoperative implant position. But why do authors choose these two groups. If you decide to compare these two groups the introduction and discussion should discuss the reason for choosing these groups and why you expect differences.
You state that the aim of the study was to analyse differences between preoperative planning and postoperative implant positioning. What is new about your study? Of course there are differences. And you even write that "differences have low clinical relevance".
The discussion should not be a repetition of the results section. Please revise lines 160-164.
Lines 170-172 should be deleted. Already included in M&M.
Lines 174-177: How can you state this if you haven't compared your results to free hand insertion?
Lines 183-185: A preoperative analysis of the bone quality is also possible with free hand insertion. The benefit is therefore not exclusive for guided implantology.
English language needs to be improved throughout.
Author Response
Please emphazise more on the intention to compare both groups. Why is it relevant? This has not been expressed sufficiently
Discussion:
The aim of the study is not clear. Authors state that it should reveal differences between präoperative planning and postoperative implant position. But why do authors choose these two groups. If you decide to compare these two groups the introduction and discussion should discuss the reason for choosing these groups and why you expect differences.
Thank you for the comments. We modified the introduction and the discussion trying to explain why we chose to compare the two groups and focusing more on the differences between the groups.
Introduction:
“There are also different protocols in the literature concerning the timing of implant insertion. Immediate (or post-extractive) implants are defined as those placed in a fresh extraction socket just after tooth extraction, immediate-delayed implants are those placed in an extraction socket within 8 weeks after tooth extraction, and delayed implants are any implants placed at least 2 months after tooth extraction [19]. Previous studies showed that there is no difference between these in terms of success rate and complications, while the best aesthetic result was obtained with post-extractive implants [20,21]. However, there are no studies that assess the accuracy of implant insertion with the computer-guided technique by comparing immediate and delayed protocol.”
Discussion:
“The only statistically significant mean difference between the group was for mesiodistal deviation at implant head. This could be explained by the lower amount of bone available to stabilise the implant in group 1 compared to group 2. Since the implant stabilised mainly in the apical portion, there may be less primary implant stability and it is possible that the tightening of the healing screw alone may have caused this difference.”
You state that the aim of the study was to analyse differences between preoperative planning and postoperative implant positioning. What is new about your study? Of course there are differences. And you even write that "differences have low clinical relevance".
Thank you for the comments. The aim of the study was to quantify these differences to try to establish whether they have clinical relevance and to compare two different protocols of insertion. Our findings seem to demonstrate that, although there are some statistically significant values, the differences are clinically insignificant. We have tried to change part of the text to make this concept clearer:
“The results of our study showed that computer-guided implant surgery in the aesthetic area had an optimal precision because it allowed an implant placement with a minimal deviation of the parameters considered in this study to three-dimensionally evaluate and compare the virtual and the real position of the implant. Indeed, the differences between the pre-operative planning and the implant placement resulted statistically significant for two parameters in both groups: the mean differences in the implant axis were 1.04° in group 1 and 1.18° in group 2, while the mean differences in the mesiodistal deviation at implant apex were 0.56 mm in group 1 and 0.53 mm in group 2. Nevertheless, despite the statistical significance, the size of these differences seems to have a very low clinical relevance.”
The discussion should not be a repetition of the results section. Please revise lines 160-164.
Thank you for the comment. We changed these lines as stated in the previous comment.
Lines 170-172 should be deleted. Already included in M&M.
Thank you for the suggestion. We deleted these lines.
Lines 174-177: How can you state this if you haven't compared your results to free hand insertion?
Thank you for the comment. The aim of our study was not to compare the precision of computer-guided implant insertion with freehand insertion but rather to investigate the existence of any deviations between the ideal three-dimensional position of the implant screw (digitally designed) and the one actually occupied in the patient's bone by insertion guided by a 3D printed template. As you rightly noted, from the study we carried out we cannot say that the guided technique is more precise than the freehand technique because we deliberately did not compare the two groups. However, given the standards of accuracy found in our study, it is our opinion that we should prefer computer-guided implant placement to freehand implant placement as found in the study by Smirktan et al. We modified the text of the manuscript to better explain this concept:
“The results of a randomised control trial conducted by Smitkarn et al. demonstrated that computer guided implant placement was more accurate if compared with freehand implant placement and for these reasons this technique should be preferred by clinicians [23]. Our findings were consistent with this study, indicating that the computer-guided implant surgery is accurate and predictable.”
Lines 183-185: A preoperative analysis of the bone quality is also possible with free hand insertion. The benefit is therefore not exclusive for guided implantology.
Thank you for the comment. We agree that pre-operative analysis of bone quality is also possible with freehand insertion, the advantage is therefore not exclusive to computer guided implantology.
This analysis is possible both pre-operatively from viewing radiographic images and intraoperatively by assessing the shear resistance encountered by the osteotomy drills. However, in our study, we have specified that an assessment of the bioavailability (not the quality) of the bone at the time of implant insertion is well evident and measurable if a digital pre-surgical planning is performed. In fact, on dedicated software it is possible to virtually insert the implant screw in the ideal position and see beforehand whether the residual bone quantity is sufficient to adequately and safely surround the implant without the need to plan regeneration procedures. This is, in our opinion, an advantage of pre-operative digital planning that could, however, be considered exclusive if the clinician's objective is to visualize the virtual positioning of the implant screw in the alveolar bone in function of the emergence of the future definitive prosthetic crown. We modified the manuscript to try to explain this better:
“Another advantage of performing preoperative digital planning for computer-guided surgery is the preliminary assessment of bone bioavailability at the implant insertion site. In fact, on dedicated software, it is possible to virtually insert the implant screw to visualize its ideal position, to assess if residual bone quantity is sufficient to safely accommodate the implant or there is a need to plan regeneration procedures, and to plan the future definitive prosthetic crown [26].”
English language needs to be improved throughout.
We tried to improve our English with the help of a native speaker.
Round 2
Reviewer 5 Report
Dear Authors,
thank you for addressing my comments. I think the manuscript has now been improved.
