Nizam N, et al. – The present split–mouth histological and histomorphometric study focused on examining the impact of leukocyte and platelet–rich fibrin (L–PRF) in combination with deproteinized bovine bone mineral (DBBM) on bone regeneration in maxillary sinus augmentation. It was concluded that both techniques were powerful for maxillary sinus augmentation, and after 6 months of healing, the addition of L–PRF in DBBM did not improve the amount of regenerated bone or the amount of the graft integrated into the newly formed bone under histological and histomorphometric evaluation.