DFDBA With or Without Platelet‐Rich Fibrin in Maxillary Sinus Augmentation: A Randomized Split‐Mouth Clinical Trial

ABSTRACT Objectives To compare histologic and histomorphometric outcomes after bilateral lateral maxillary sinus augmentation with demineralized freeze‐dried bone allograft (DFDBA) alone versus DFDBA combined with platelet‐rich fibrin (PRF), and to report 1‐year prosthetic follow‐up of the restored implants. Materials and Methods This randomized split‐mouth clinical trial included subjects requiring bilateral lateral maxillary sinus augmentation before implant placement. In each subject, one sinus was randomly assigned to DFDBA alone and the contralateral sinus to DFDBA combined with leukocyte‐ and platelet‐rich fibrin (L‐PRF) and injectable PRF (i‐PRF). Bone biopsy specimens were harvested at the clinically relevant 6‐month implant placement time point. The primary outcome was newly formed bone. Secondary histomorphometric outcomes were residual graft material, connective tissue, and fibrosis; inflammation and necrosis were assessed histologically. Clinical and radiographic prosthetic follow‐up was performed 1 year after definitive prosthetic loading. Paired comparisons were performed using the Wilcoxon signed‐rank test. Results Of 24 enrolled subjects, 21 completed follow‐up and contributed 42 sinus sites to the paired analysis. Median newly formed bone was 48.72% (IQR, 33.33%–63.33%) on the PRF side and 45.76% (IQR, 37.14%–54.90%) on the non‐PRF side ( p = 0.5). Residual graft material was 6.74% versus 4.23% ( p = 0.2), connective tissue was 31.48% versus 36.92% ( p = 0.016), and fibrosis was 3.42% versus 2.56% ( p > 0.9). No inflammation or necrosis was observed. Following replacement of one implant that failed before prosthetic loading, all definitively restored implants remained functional during the 1‐year prosthetic follow‐up. Clinical and radiographic follow‐up was uneventful, and no biologic or prosthetic complications requiring intervention were observed. Conclusions Adding PRF to DFDBA did not significantly increase newly formed bone at the 6‐month implant placement time point. The lower connective tissue proportion on the PRF side may suggest altered tissue maturation; however, this secondary finding should be interpreted cautiously. Definitively restored implants showed 100% prosthetic survival during 1‐year follow‐up. Trial Registration ClinicalTrials.gov Identifier: NCT07348198; https://clinicaltrials.gov/study/NCT07348198 . This clinical trial was not registered prior to participant recruitment and randomization.