Masticatory Efficacy Following Implant Rehabilitation: Objective Assessment and Patient Perception Through Two-Color Mixing Test and Viewgum^® Software

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The article addresses an important clinical problem, which is the lack of consistency between the subjective assessment of chewing efficiency and objective measurements of this function in patients undergoing implant rehabilitation. The aim of the authors was to examine whether patients with minor tooth loss (up to 4 missing teeth) undergoing implant treatment improve chewing measured both subjectively (VAS) and objectively (VOH). The study was conducted using a two-color chewing test and Viewgum® software, which makes it consistent with current trends in the assessment of chewing function. The introduction to the article is clear, substantively grounded, and leads the reader from the basic assumptions of masticatory function to the purpose of the study. The literature review is extensive and well-documented, taking into account both classical and modern methods of measuring masticatory function and the importance of subjective indicators of the patient's health assessment (patient-reported outcomes). The study methodology was described with great care. Strict inclusion and exclusion criteria were established, and the data collection procedure was well standardized. Appropriate research tools were used: a color mixing test (Hue-Check Gum®), Viewgum® software, and a 100-mm visual analog scale (VAS) for subjective assessment. Calibration of the data analyzer was confirmed by the coefficient of agreement (Cronbach α = 0.91). Statistical analysis was adequate - due to the lack of normality of the distribution of variables, nonparametric tests (Wilcoxon) were used, and the results were presented in a clear and detailed manner (means, standard deviations, CI, p-values).

The results showed statistically significant improvement in both VOH (reduction from 0.462 to 0.438) and VAS (increase from 3.46 to 7.29). At the same time, there was no correlation between subjective and objective results, which the authors correctly interpret as evidence that both measures reflect different aspects of masticatory function. Figures and tables complete the whole and facilitate the interpretation of the results.

 

Study flaws and limitations

Despite the high scientific quality and methodological correctness, the study has several notable limitations that should be taken into account:

 

Small number of participants – the sample includes only 30 patients from one university clinic, which limits the possibility of generalizing the results to a wider population. There is also a lack of representativeness data (age, socioeconomic status, education).

 

No control group – the study did not use a comparison group (e.g. with removable dentures or bridges), which makes it impossible to assess the relative effectiveness of implants versus other treatment methods.

 

Short-term follow-up – the study only assesses the early effects of treatment. There is no long-term data (6–12 months after treatment) that could show the durability of the improvement in chewing function.

 

Limitations of the VOH method – photos for colour analysis were taken with a smartphone, which, although consistent with the literature, may generate errors in colour analysis (light, angle, sharpness), especially at higher VOH values.

 

Lack of validated subjective questionnaires – only the general VAS scale was used, whereas validated tools such as CFQ, GOHAI or OHIP-14, which allow for the assessment of specific aspects of chewing function and the quality of life of patients, would be more reliable.

 

VAS measurement without reading error control – the VAS scale was read manually using a ruler, which may be a source of measurement errors if double reading or independent assessment was not ensured.

 

Final conclusions

The article is well written, clear and methodically correct. It is a valuable contribution to research on the effectiveness of implant prosthetics in relation to masticatory function. The presented results are convincing and consistent with the current literature, but methodological limitations (small sample, no control group, short follow-up period) limit their interpretation and generalizability. More complex statistical and psychometric analyses are also missing. Perhaps the authors are able to fill in the gaps I mentioned above - this would definitely improve its quality and scientific tone. However, the article is suitable for publication after taking into account the limitations in the discussion section and possible minor editorial corrections.

Comments for author File: Comments.pdf

Author Response

Please see attached file

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The article aims to evaluate the differences in masticatory efficiency following implant rehabilitation using both objective and subjective tests. The manuscript is well-structured but requires some clarifications prior to publication:

• Participant Selection: The exclusion criteria should not simply be a negative restatement of the inclusion criteria. These should be reformulated and should include important factors relevant to the study, such as exclusion of patients with metabolic diseases, vitamin D deficiency, etc.

• Data Collection: The authors mention that medical data were collected, but it is necessary to specify which data. It appears that some relevant information was not explicitly reported, such as implant locations, whether the implant is a single unit, and whether there is a natural opposing tooth, among others.

• Sample Heterogeneity: The lack of sample standardization represents a major bias when attempting to establish a database for comparing two diagnostic methods.

• Objective Test Choice: What was the rationale for choosing the objective test (Hue-check gum) over the gold standard? This should be justified.

• Gender Perception Differences: Although the sample did not show differences in sex distribution, this does not imply that perception of masticatory efficiency is the same. The literature consistently reports that females tend to perceive masticatory function differently, often showing lower QoL scores. Therefore, results should be stratified and presented by sex.

• Follow-up Duration: The authors mention a short follow-up period but do not specify the duration. This should be clearly stated, as muscle activity can change over time and potentially affect masticatory efficiency.

• Implant Location: The authors state that most implants were placed in the posterior region. However, it is important to specify which sectors exactly. If the remaining 20.8% were placed in the anterior region, they may not significantly impact masticatory efficiency, which could introduce bias into the study.

• Prosthetic Details: It is important to indicate whether the implants were single units or bridges and whether they had natural antagonist dentition, as this can affect the results.

• Surgical Consistency: Were all implants placed by the same surgeon under the same conditions? For example, were additional surgical procedures like bone grafts used? This should be clarified.

• Type of Prosthetic Rehabilitation: Was the same type of prosthetic material used (ceramic crown, metal-ceramic, acrylic, etc.)? The material type may also influence masticatory efficiency.

• Discussion Section: The authors should expand on the discussion to include:

  1. How the number of implants may influence the results (placing one implant is different from placing four),

  2. The impact of implant placement region,

  3. Possible reasons for discrepancies between objective and subjective methods,

  4. The implications of a short follow-up period on assessing masticatory efficiency.

Author Response

Please see attached file

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The title’s phrasing (“Objectivity vs. Perception”) implies a direct comparison that the study design does not fully address, as it evaluates both metrics separately rather than contrasting them

The abstract states a 15% dropout rate but reports 7/37 exclusions (19%), creating confusion. Please correct the math.

Missing implant dimensions (length/diameter) and loading protocols (immediate/delayed

iPhone 11 Pro camera settings (e.g., lighting, ISO) are unspecified, risking variability in image analysis. Provide settings and documentation enviroment (since you described details of the camera, which is less relevant than photo settings).

The abstract references a 0–10 scale, while the methods describe 0–100 mm. Please consistently use one scale (e.g., 0–100 mm) throughout.

The introduction cites cognitive decline but does not contextualize its relevance to masticatory efficiency.  Please remove tangential references or elaborate on mechanisms (e.g., nutritional pathways).

No exploration of why subjective satisfaction (VAS) and objective efficiency (VOH) lack correlation (e.g., psychological adaptation, occlusal force).

VOH decreased by only 0.024 units post-treatment—statistically significant but clinically marginal. Please address effect size and practical implications.

No declaration regarding affiliations with Hue-Check Gum® or Viewgum® suppliers. Add a conflict of interest statement.

The conclusion does not acknowledge study limitations (e.g., single-center design, short follow-up) - please add limitations of the study.

The study provides valuable insights into masticatory efficiency assessment but requires tighter methodological reporting and deeper contextualization of findings. Addressing these issues will enhance translational impact.

Author Response

Please review the attached pdf document

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

All my comments were taken into account, the authors made corrections and created a valuable and interesting work.

Reviewer 3 Report

Comments and Suggestions for Authors

Much better thank you and congratulations to authors