Boosting early bone healing by freeze-dried bovine leukocyte-platelet rich fibrin and nanohydroxyapatite in rabbit: histopathological, molecular, and Raman spectroscopy analysis.

INTRODUCTION: Globally, millions suffer from bone fractures every year, with substantial clinical consequences. Intervention is crucial when healing mechanisms are ineffective. Leukocyte-platelet rich fibrin (L-PRF), by its rapid, simple, and cost-effective preparation methodology alongside a calcium phosphate-based compound such as nanohydroxyapatite may favorably impact clinical practice. SOURCE OF DATA: A critical-sized radius bone defect was produced in 25 White New Zealand rabbits divided into five groups (n = 5 per group) including untreated, autograft, nanohydroxyapatite scaffold, bovine lyophilized L-PRF, and nanohydroxyapatite and L-PRF simultaneously. The defects were evaluated 7 days postsurgery by histopathological, molecular, and Raman spectroscopy evaluations. AREAS OF AGREEMENT: Platelet and growth factor content of lyophilized L-PRF powder stimulate cell proliferation and differentiation, and extracellular matrix production. Nanohydroxyapatite scaffold and lyophilized L-PRF powder could effectively enhance early bone regeneration. AREAS OF CONTROVERSY: While the autograft group was expected to perform best, as the gold standard of repair, the lyophilized L-PRF group performed best in some indicators of extracellular matrix production, such as matrix-to-mineral ratio and carbonate-to-phosphate ratio. GROWING POINTS: Nanohydroxyapatite scaffold played as a mechanical strength provider and had a lesser role in stimulating biological repair responses, in the short term, while L-PRF significantly enhanced cell proliferation and differentiation and extracellular matrix production by releasing osteogenic factors. AREAS TIMELY FOR DEVELOPING RESEARCH: The long-term effects of lyophilized L-PRF on bone repair, duration of platelet growth factor release from L-PRF, injecting fresh L-PRF at periodic intervals, and using lyophilized L-PRF alongside other bone-stimulating scaffolds should be addressed in future studies.