Aim. This study aimed to evaluate the structural composition of biopsy samples from the augmented maxillary sinus region using the NanoGraft biomaterial.

Materials and methods. Biopsy specimens from sinus lift procedures involving NanoGraft were histologically examined. Samples were fixed in 10 % neutral buffered formalin for 48–72 hours, decalcified using a rapid decalcifier (Kaltek, Italy), and processed in paraffin using an automated tissue processor (Milestone LOGOS, Milestone, Italy). Paraffin blocks were prepared with the HistoStar embedding workstation (Thermo Fisher Scientific, USA), and 4 µm serial sections were obtained using the Thermo Scientific HM 340E rotary microtome. Sections were stained with hematoxylin and eosin (Dako CoverStainer, Agilent, USA), and toluidine blue staining was performed manually. Morphological analysis was carried out using a Leica light microscope to assess bone structure, surrounding connective tissue, resorption dynamics, and new bone formation.

Results. All samples revealed newly formed trabecular bone, active osteogenesis, and progressive remodeling, with replacement of coarse fibrous bone by lamellar bone containing osteons. No significant inflammatory response to the biomaterial was observed.

Conclusions. NanoGraft exhibited high biocompatibility, along with osteoinductive and biostimulatory properties, making it a promising material for maxillary sinus augmentation procedures.