Treatment of Unfavorable Intrabony Defects with Autogenous Bone Graft in Combination with Leukocyte- and Platelet-Rich Fibrin or Collagen Membranes: A Non-Inferiority Study

Background and Objectives: Unfavorable intrabony defects (IBDs) are associated with the progression of periodontal disease and tooth loss. Growing scientific evidence has demonstrated the effectiveness of platelet concentrations in periodontal treatment. The aim of our study was to demonstrate the non-inferiority of an autogenous bone graft (ABG) associated with leukocyte- and platelet-rich fibrin (L-PRF) compared to ABG + Collagen Membrane in the treatment of IBDs. Material and Methods: Sixty-four patients with at least one IBD were randomly assigned to two groups: ABG+L-PRF and CM+ABG. Clinical and radiographic evaluations were performed at baseline and 12-month follow-up. Clinical attachment level (CAL), gingival recession (GR), probing pocket depth (PPD), and radiograph defect bone level (DBL) were compared between the two treatments. To evaluate the effectiveness of ABG+L-PRF, a non-inferiority margin of =1 mm (−1 mm for GR) was chosen; a second non-inferiority margin of =0.5 mm (−0.5 mm for GR) was set for clinical relevance. Results: At 12-month follow up, both treatments showed clinical and radiographic improvements. The 90% confidence intervals of the CM+ABG–L-PRF+ABG mean difference for CAL gain (−0.0564 mm −0.316 to 0.203), DBL gain (−0.433 mm −0.721 to −0.145), and PPD reduction (0.232 mm 0.015 to 0.449) were below the 0.5 mm non-inferiority margin; the GR increase (0.255 mm 0.0645 to 0.445) stayed above the −0.5 mm. Conclusions: the L-PRF+ABG treatment of unfavorable IBDs is non-inferior with respect to the CM+ABG therapy for CAL gain, but with a lower GR, a slightly higher PPD, and DBL gain.