Comparative Evaluation of Clinical and Radiographic Outcomes of Regenerative Endodontic Therapy Using Blood Clot Versus Platelet-Rich Fibrin Scaffolds in Immature Permanent Teeth: A Prospective Cohort Study.

Background and objective Regenerative endodontic treatment (RET) promotes continued root development in immature permanent teeth with pulp necrosis; however, the optimal scaffold for maximizing regenerative outcomes remains uncertain. The objective of this study is to compare the clinical and radiographic effectiveness of platelet-rich fibrin (PRF) and conventional blood clot scaffolds using standardized cone-beam computed tomography (CBCT)-based assessment and to identify independent predictors of regenerative success. Methods This prospective, non-randomized comparative clinical study was conducted at the Department of Pediatric Dentistry, Pacific Hospital, Udaipur, Rajasthan, India, and included 40 children with non-vital immature permanent maxillary incisors treated with RET using either a blood clot scaffold (n = 20) or a PRF scaffold (n = 20). CBCT-based radiographic analyses were performed at baseline and the 15-month follow-up. The primary outcome was the percentage increase in radiographic root area (RRA), while secondary outcomes included percentage changes in root length, apical diameter, and periapical lesion size. Clinical outcomes were evaluated throughout follow-up. Between-group comparisons were performed using independent t-tests or Mann-Whitney U tests, as appropriate, and multivariable linear regression was used to identify independent predictors of RRA improvement. Results Radiographic analysis included 37 teeth (blood clot, n = 18; PRF, n = 19). The PRF group demonstrated a significantly greater increase in RRA than the blood clot group (19.15 ± 6.22% vs. 9.72 ± 5.18%; mean difference, 9.43%; 95% confidence interval (CI), 5.86-13.00; p < 0.001; Cohen's d = 1.58). PRF also achieved significantly greater reductions in apical diameter (p = 0.028) and periapical lesion size (p < 0.001), whereas the increase in root length did not differ significantly between groups (p = 0.415). Both groups exhibited significant within-group radiographic improvement and high clinical success rates (blood clot: 90%; PRF: 95%). Multivariable regression identified PRF as the strongest independent predictor of RRA improvement (β = 9.43, p < 0.001), while larger baseline periapical lesion size was negatively associated with regenerative outcomes. Conclusions PRF was associated with significantly greater structural root maturation and periapical healing than the conventional blood clot scaffold while maintaining comparable clinical success. Standardized CBCT-based quantitative assessment supports PRF as an effective scaffold for RET and provides robust evidence to inform clinical decision-making.