Comparative Clinical Evaluation of Digital Versus Conventional Dental Impression Techniques in Implant-Supported Restorations

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

In this work, a comparative clinical study was performed on conventional dental impression techniques, involving the adoption of PVS and Polyether for impression, and the digital intra oral scanner. Clinical evaluation was performed adopting radiographic analysis during several phases (initial, post operation, temporary and final restoration and up to 5 years recall). Finally, a questionnaire was submitted to the two group under study to evaluate the satisfaction of the patients.

The paper has a good quality, and it is well written, with clear explanation of the workflow and procedures. The main novelty of the paper is the comparison of conventional and digital impression techniques in vivo, taking into account the patients’ satisfaction. References are up to date and well fit with the thematic under study.

Here are some considerations before the paper can be accepted:

I suggest inserting a comparison between the STL file generated adopting the two intra oral scanner to highlight possible differences in the digital reconstruction process.

Please, increase the character size of Figure 7 b, for 0.7 and 0.5 mm.

For future studies, this reviewer thinks that a better evaluation of the differences between the conventional and digital techniques can be conducted performing scanning of the impressions made with conventional techniques adopting the intra oral scanner. A comparison of the scanning, highlighting the differences between the conventional and digital STL, can be performed adopting specific softwares that analyse the deviation between two STL files. In this way, a quantitative analysis can be performed.

For all the previous reasons, the reviewer recommends Minor amendments of paper for publication in Prosthesis.

Author Response

Thank you for your review.Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors, the topic addressed in your article is extensively discussed in the current Scientific Literature and is supported by a substantial body of evidence. I have to suggest some changes that will improve the fluency of the text and reader understanding, in full adherence to the article writing guidelines.

1. Abstract should contain the following headings: Background (or Objectives), Methods, Results, and Conclusions. Please, make all the requested edits.
2. Abstract should be concise, no more than approximately 250 words. Please check carefully this section of your manuscript.
3. There is no mention in the abstract and in Materials and Methods about which quantitative parameters (e.g. linear distances, angular values...) and corresponding SI Units (International System of Unit of measure) were considered for the study outcomes. 
4. How was the appropriate sample size for the study statistically determined? Please discuss this issue.
5. Fig 1 D needs to be flipped horizontally to match the image Fig 1 B.
6. Group A included impressions taken using open or closed tray techniquess, PVS or Polyether: thus, all measurements recorded for Group A lack homogeneity of experimental conditions. A SINGLE group must correspond to a SINGLE treatment; it cannot be a combination of different techniques. It is well known in Dental Literature that the impression on implants can be influenced by factors such as the different chemical-physical properties of the impression materials and the technique used. The same applies to group B where two different scanners were used, with different protocols of impression making.

Author Response

Thamk you for your review.Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Dear Authors,

This study compared digital and conventional impression methods in implant-supported restorations. Forty cases were analyzed: 20 with elastomeric materials and 20 with intraoral scanners (TRIOS 3, Medit i700). Accuracy and passive fit were assessed radiographically and with the Sheffield test; workflow efficiency was measured by chairside time; patient satisfaction was recorded using a VAS questionnaire. Digital impressions showed fewer misfits (15% vs. 25%), reduced time (13 vs. 27 minutes), and no final adjustments. Patients also reported higher comfort and esthetic satisfaction. The findings suggest digital workflows are more efficient and patient-preferred, though conventional methods remain valid when digital tools are unavailable.

 

However, there are some suggestions to improve the quality of the manuscript:

• Major editing of English language required.
• Punctuation should be corrected.
• Provide a clearer cost-benefit analysis of digital versus conventional workflows.
• The introduction could be improved and expanded to provide a more comprehensive background and context for the study.
• Strengthen the conclusion by summarizing key findings and emphasizing the clinical implications and limitations of the study.
• Although the study explicitly reports inclusion of only partially edentulous patients, one figure appears to show a fully edentulous case. Please clarify or replace the image to ensure consistency with the stated methodology.
• Please add to the limitations that the scanners used (TRIOS 3 and Medit i700) are previous-generation devices, and results may not fully reflect the performance of newer systems.
• Please acknowledge in the limitations that patients were allocated to separate groups, without a crossover or split-mouth design. This reduces direct intra-patient comparability and should be considered as a methodological limitation.
• The Discussion section would benefit from a more comprehensive integration of existing literature. At present, the authors primarily focus on their own results, with only limited references to previous studies. To strengthen the manuscript, the findings should be critically compared with the broader body of evidence, including randomized clinical trials, systematic reviews, and consensus statements. Expanding the discussion in this way would place the present study in a clearer scientific context and highlight its actual contribution to the field.

Author Response

Thank you for your review.Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Dear Authors,

Your scientific work deserves congratulations!

Please pay attention regarding the following aspects:

- The discussion part of the manuscript should be improved by adding the findings of other researchers, as only four articles are comparatively presented.

- The clinical relevance of the study results, the limitations of the research, and future studies should be emphasized more at the end of discussion section.

- The conclusions are pertinent and in accordance with the results, but they are too detailed; the conclusions section should be more concise, and the outcome values can be transferred to the results section.

- Out of the 45 consistent bibliographic titles of the manuscript, only 18 titles are older than five years, but all are relevant.

I propose the publication of this manuscript after minor revisions, according to the aforementioned observations.

 

Author Response

Thank you for your review.Please see the attachment.

Author Response File: Author Response.docx

Reviewer 5 Report

Comments and Suggestions for Authors

1)The paper is well-structured and presents meaningful clinical evidence comparing digital and conventional impressions.

2)Consider expanding the discussion on economic implications and accessibility of digital scanners, which could add practical value.

3)In future studies, a prospective or crossover design could further strengthen causal inferences.

4)Minor suggestion: include a summary table comparing the main outcomes (misfit rates, time efficiency, and patient satisfaction) for faster reader interpretation.

Author Response

Thank you for your review.

Please find in attachment our response.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors, I regret to inform you that I do not consider your clinical study suitable for publication. There are serious ethical and methodological issues to justify this final rejection.

You stated that you conducted a retrospective study, although the text seems to describe a prospective, non-randomized, non-controlled study instead. (I don't understand why you did this).

You subjected the patients to numerous x-rays taken at frequent intervals, as documented in Figure 6 a-j (OPGs, Orthopantomography), in addition to CBCT (cone-beam computed tomography), and intraoral x-rays, for the purpose of evaluating measurement parameters that are obtainable with simple, low-dose intraoral x-rays. You did not specify in the text how many CBCT scans, OPG scans, and intraoral x-rays each patient received, therefore it is difficult to estimate the impact of the radiation dose to which each patient was unjustifiably exposed over time. You did not specify how many operators performed the Sheffield test, whether they were calibrated before the study began to obtain comparable and consistent measurements, or whether, as I believe, there was a high risk of subjectivity in the measurements (in fact, this method requires the marginal gap to be detected "by touch" and "visually," at the discretion of the individual operator).

There are no images or photographs depicting the marginal gap measurement steps on digital radiographs using appropriate software or the Sheffield test phases performed in the patient's mouth.

Persisting in mixing different materials and impression techniques in the same group A (PVS/Polymer; Open Tray/Closed Tray) as in group B without making the necessary distinctions does not help achieve controlled clinical experimental conditions. Your method, while reflecting "practical reality," loses sight of the intrinsic specificity of each technique and their effect on overall accuracy.

Author Response

For research article Comparative Clinical Evaluation of Digital Versus Conven-tional Dental Impression Techniques in Implant-Supported Restorations

 

 

Response to Reviewer 2 Comments
1. Summary
We sincerely thank Reviewer 2 for the time and effort dedicated to evaluating our manuscript. We appreciate the reviewer’s concern regarding the ethical and methodological aspects of our study. However, we respectfully clarify that the study design, data collection, and imaging protocols fully comply with ethical standards and do not involve unnecessary patient exposure or prospective interventions. The following clarifications have been added to the revised manuscript to ensure transparency and avoid any potential misinterpretation.
2. Questions for General Evaluation	Reviewer’s Evaluation	Response and Revisions
Does the introduction provide sufficient background and include all relevant references?	Not applicable	We respectfully clarify that the Introduction already provides a comprehensive and well-referenced overview of the topic. No methodological issues raised by the reviewer relate to this section; therefore, no changes were required.
Is the research design appropriate?	Not applicable	The reviewer appears to have misunderstood the study design. This investigation was retrospective, based exclusively on previously completed clinical cases. No patient was prospectively enrolled or exposed to additional procedures for the purpose of research. The data—including radiographs—were collected from existing clinical documentation and analyzed retrospectively under ethical approval (UMF “Victor Babeș” Timișoara). This clarification is now emphasized in the Materials and Methods section.
Are the methods adequately described?	Not applicable	The study methodology remains fully described. To clarify the reviewer’s concern, we have specified that all radiographic examinations (intraoral, panoramic, or CBCT) were obtained strictly for clinical purposes as part of standard diagnostic and prosthetic protocols—not for research exposure. The analysis used only the available records, without repeating or adding radiographs. Additionally, we confirmed that the Sheffield test was performed by calibrated clinicians within the same clinical setting. These clarifications have been added in the Methods section.
Are the results clearly presented?	Not applicable	The results were already structured according to MDPI standards, with objective reporting of all quantitative data. No modifications were required.
Are the conclusions supported by the results?	Not applicable	The Conclusions remain consistent with the data and have been retained in their current form. However, to ensure transparency, we have reiterated that the study design was retrospective and observational, with no additional patient exposure.
Are all figures and tables clear and well-presented?	Not applicable	All figures and tables have been reviewed for clarity. Figure 6a–j, referenced by the reviewer, represents retrospective documentation of clinical follow-up and not repeated radiation exposures. Captions were revised slightly to make this explicit.
3. Point-by-point response to Comments and Suggestions for Authors
Comments 1: You stated that you conducted a retrospective study, although the text seems to describe a prospective, non-randomized, non-controlled study instead. (I don't understand why you did this).
Response 1: We appreciate the reviewer’s concern and the opportunity to clarify this important point. The study is indeed retrospective, as explicitly stated in the Materials and Methods section. No patient was prospectively enrolled, and no additional diagnostic or therapeutic procedure was performed for the purposes of this research. All data were obtained from existing clinical records of patients previously treated in our clinic. To enhance clarity, we have inserted the following statement in the Materials and Methods section: “This was a retrospective clinical analysis based exclusively on previously completed implant-supported restoration cases. No patient was prospectively enrolled or exposed to additional diagnostic procedures for the purpose of this study.”
Comments 2: You subjected the patients to numerous x-rays taken at frequent intervals … It is difficult to estimate the impact of the radiation dose …
Response 2: We thank the reviewer for raising this concern. All radiographic examinations analyzed in this study (periapical, panoramic, and CBCT) were performed strictly as part of standard diagnostic and therapeutic protocols. No additional exposures were taken for research purposes. The study team only analyzed archived clinical images obtained during routine follow-up. A clarifying statement has been added to the Materials and Methods section: “All radiographic examinations (periapical, panoramic, or CBCT) included in the analysis were obtained strictly for clinical diagnostic and follow-up purposes according to standard treatment protocols. No supplementary exposures were performed for research reasons. Data were analyzed retrospectively from existing clinical records.” In addition, the Figure 6 caption was updated to emphasize that all images were part of routine care and not additional research exposures.
Comments 3: You did not specify how many operators performed the Sheffield test or whether they were calibrated.
Response 3: We agree that inter-operator calibration is important for methodological consistency. The Sheffield test was performed by two calibrated clinicians (Dr. Antonie Sergiu and Dr. Borsanu Ioan), both trained in the same implant prosthodontic protocol. Both are authors of this article. A clarification has been added to the Evaluation methods section, right after Figure 7: “The Sheffield test was performed by the two experienced clinicians, Dr. Ioan Borșanu and Dr. Sergiu-Manuel Antonie, both trained in the same implant prosthodontic protocol to ensure consistent tactile and visual assessment of passive fit.”.
Comments 4: There are no images or photographs depicting the marginal gap measurement steps ….
Response 4: We appreciate this remark and agree that additional methodological clarity is helpful. Marginal gap measurements were performed directly on digital panoramic and intraoral radiographs using the Planmeca Romexis software, which enables calibrated linear distance analysis at the implant–abutment interface. Figure 7 illustrates representative cases showing accurate fit and measurable misfit (0.7 mm and 0.5 mm, respectively). To clarify this in the manuscript, the following sentence was introduced after figure 7: “Measurements were performed directly within the Planmeca Romexis software, which allows for calibrated linear distance evaluation on digital panoramic images.”
Comments 5: Persisting in mixing different materials and impression techniques in the same group A (PVS/Polyether; open tray/closed tray) as in group B … loses sight of the intrinsic specificity of each technique …
Response 5: We respectfully note that the grouping strategy was intentional, reflecting real-world clinical practice rather than an artificially isolated experimental setup. Group A represented the conventional workflow most commonly adopted in daily prosthodontic activity (using PVS or polyether, open- or closed-tray methods), while Group B represented the digital workflow (TRIOS 3 or Medit i700 scanners). To address this concern, we have clarified the rationale in the Materials and Methods section and acknowledged this methodological heterogeneity as a study limitation in both the Discussion and Conclusions.
4. Response to Comments on the Quality of English Language
Point 1:
Response 1: The manuscript has been carefully reviewed for clarity and precision of language. Minor editorial refinements were applied to improve flow and ensure the consistent use of technical terminology (e.g., “retrospective design,” “clinical evaluation,” and “radiographic measurement”). The English was double-checked throughout, ensuring that all methodological descriptions and results are now expressed with greater clarity and academic tone.
5. Additional clarifications
[All necessary clarifications raised by the reviewer have been addressed in detail in the point-by-point responses above. Specifically, we have: Clarified that this is a retrospective study, analyzing data from previously completed clinical cases, where all radiographic examinations were originally performed for diagnostic and therapeutic purposes, in full compliance with ethical standards. Added details on examiner calibration — the Sheffield test was performed by two experienced clinicians (Dr. Ioan Borșanu and Dr. Sergiu Antonie) following standardized clinical procedures. Specified the radiographic measurement method, indicating that all marginal gap measurements were performed directly in Planmeca Romexis® software on existing radiographs. Acknowledged methodological heterogeneity (different materials and scanners) as an inherent aspect of real-world clinical practice, now explicitly discussed as a limitation. We thank the reviewer for the critical reading and constructive observations. These clarifications have strengthened the transparency and methodological completeness of the manuscript while maintaining the integrity of the original research design.]

 

 

 

 

Author Response File: Author Response.pdf

Round 3

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors, I thank you for specifying that the patients were not subjected to excessive radiation doses but only those strictly necessary for clinical purposes, as part of standard diagnostic and prosthetic protocols. However, I regret to inform you that I cannot recommend publication of your article in this Journal. Retrospective studies represent a valuable resource in medical research and are particularly useful for assessing relationships between exposures and clinical outcomes, leveraging pre-existing data. However, this type of study has significant limitations in the quality and quantity of data available for analysis. As I mentioned in the previous review, the topic addressed in this article is extensively discussed in the current literature and is supported by a substantial body of evidence. Currently, there is a high demand for studies with greater statistical power and long-term follow-up (RCTs) to partly or fully confirm/reject what is currently known regarding the comparison of traditional versus digital impressions. Your study inherently has limitations, such as the lack of a priori selection of the study population. Rarely in dental literature it is possible to find studies where different materials and impression techniques are included in the same group (group A: PVS/Polymer + Open Tray/Closed Tray; group B: two different IOs) without making the appropriate distinctions.

Author Response

Thank you for your review.

Please find in attachment our response

Author Response File: Author Response.docx