Comment on “Clinical and radiographic assessment of effect of platelet‐rich fibrin on dental implant osseointegration – A split mouth randomized clinical trial”

Dear Editor,

We read with great interest the article by Ali et al. titled, “Clinical and radiographic assessment of effect of platelet‐rich fibrin on dental implant osseointegration– A split mouth randomized clinical trial”. ¹ The study addresses an important topic in implant dentistry. Based on our experience and research in this field, we would like to highlight a few major and minor concerns which need to be addressed by the authors. ² , ³

Firstly, the authors have described their research as a randomized split‐mouth study design, which is also stated as the highlight of their study. However, a true split‐mouth design requires site‐level randomization within the same patient, typically between contralateral sides, with appropriate paired statistical analysis. ⁴ In the present study, implants were placed with or without platelet‐rich fibrin (PRF) in the maxilla, mandible, or both, across varying numbers of patients, and were analysed collectively. This suggests a potential misapplication of the split‐mouth methodology, which may introduce variability and reduce the reliability of comparisons. As per our understanding, a statistical test such as repeated measures ANOVA would have generated more meaningful evidence rather than independent t‐tests or Mann–Whitney U tests for intergroup comparisons for a split‐mouth design, where paired statistical analyses are required. Information regarding sample size calculation or statistical power analysis is also missing, making it difficult to assess whether the study was adequately powered to detect clinically meaningful differences.

Additionally, the study does not specify whether implants were placed in anterior or posterior regions. This distinction is critical, as bone density and quality differ significantly between these regions, potentially influencing outcome and its interpretation. ⁵ Furthermore, the authors have not clearly specified whether the implants placed were adjacent to each other or at distant sites. This is an important factor, as the proximity of implants can influence peri‐implant bone loss, particularly in cases of adjacent implant placement where inter‐implant bone remodeling may occur.

The inclusion criteria of the study appear contradictory. The study mentions the inclusion of fully edentulous patients while also referring to patients with a single missing tooth or free‐end situations. These conditions are mutually exclusive and require clarification. Another inconsistency was noticed in the reported implant dimensions: while the authors state that implants of 11.5 mm length were used in all participants, the provided figure (Figure 1 of manuscript) ¹ appears to show implants measuring approximately 13 mm from shoulder to apex. Finding subjects who would fit into the inclusion criterion and who would be suitable for specific implant dimensions is difficult in a real‐time clinical scenario.

The assessment of peri‐implant bone density using cone‐beam computed tomography (CBCT) gray values is another area of concern. CBCT does not provide standardized Hounsfield Units, and gray values are highly influenced by factors such as limited field of view, beam hardening, scatter, and polychromatic X‐rays, limiting the reliability and reproducibility of the measurements. ⁶ , ⁷ The authors have stated this as a limitation, but could have justified not using the conversion formula as it would have given clinically more relevant information. It can be assumed that all the implants were placed freehand as use of any surgical guide is not mentioned by the authors. A slight deviation of the implant towards cortical bone or medullary bone can significantly impact the gray values obtained in CBCT and affect the distribution of the data during statistical analysis.

In addition, the term “flute” has been used to describe implant reference points (e.g., “from the implant's first flute to the implant apex”). However, in implant dentistry, the correct term is “thread,” as dental implants are characterized by threads rather than flutes, especially in the crestal part. Moreover, implant threads are not clearly discernible on CBCT images due to resolution limitations and metal artifacts, making their use as precise reference landmarks questionable.

Another major concern that could not be ignored was that the implants were not subjected to progressive or functional loading till one year after implant placement. While ethical approval and patient consent were obtained, such prolonged unloading is not consistent with current implantology practices, where loading is typically performed within 3–6 months. Leaving patients without prosthetic rehabilitation for such an extended period may lead to complications such as supraeruption of the antagonist, tilting of adjacent teeth, or detrimental effects on temporomandibular joints. Additionally, loading protocols themselves can influence peri‐implant bone density and marginal bone level changes. ⁸

Last but not least, the authors stated that the aim of their study was to analyze the function of PRF in the osseointegration of dental implants from a clinical and radiographic point of view. The benefit of PRF has been documented in promoting soft tissue healing, while evidence supporting its role in bone regeneration remains inconsistent. ⁹ , ¹⁰ How the growth factors released from PRF led to an increase in the bone density around delayed implants, and how it may have affected the osseointegration of implants was not discussed adequately by the authors. Furthermore, the manuscript does not adequately describe PRF handling protocols, and the practice of removing red blood cell remnants using gauze is unconventional. The absence of clinical photographs limits the ability to fully understand the procedural aspects and validate the reported outcomes.

In conclusion, while the study explores a clinically relevant topic, addressing these methodological and reporting concerns would significantly enhance its scientific rigor and clinical applicability.