Conclusions
Within the limitations of this study, the present data seem to support the effectiveness of using GTR membranes in association with L-PRF for improving the intrabony defect fill. On a bio-molecular level, periodontal defect ecology failed to maintain any L-PRF claimed extra physiologic concentration of growth factors (PDGF and VEGF) even following collagen barrier membrane protection. Future studies with larger sample size as well as testing other subtypes of PRF are recommended.