BG-58S macrospheres produced using BG powder synthesized by alkali-mediated sol–gel process and different phosphorus precursor

Purpose Bioactive glass (BG) spheres with uniform shape and specific size variation are allowed to be packed into a 3D arrangement, which results in an open porosity that improves bone growth. Methods BG-58S macrospheres were produced using BG powder synthesized by alkali-mediated sol–gel process and different phosphorus precursors (TEP or phosphoric acid-AF). Macrospheres (MAF-1 M, MAF-2 M, MTEP-1 M, and MTEP-2 M) were characterized as to surface morphology and size, theoretical density, and specific surface area/pore size distribution. In vitro bioactivity was evaluated in simulated body fluid (SBF). In vitro tests were conducted (for MAF-2 M and MTEP-2 M) as cell viability, total protein content, determination of alkaline phosphatase, cell adhesion by means of SEM, and mineralization nodules formation compared to commercial product (BG-45S5). Biological performance was verified through histological and histomorphometric analyses around the samples: BG-45S5, MTEP-2 M, and control (clot). Results All physicochemical characterizations demonstrated favorable macrospheres for application in bone grafting. MTEP-2 M and MAF-2 M showed higher cell viability and total protein content when compared to BG-45S5 with a statisti- cal difference (p < 0.05); however, no statistical difference was detected among the groups regarding the determination of alkaline phosphatase (p > 0.05). Cells adhered to the surface were observed for all samples as well as nodules of minerali- zation. The results referring to in vivo biological assays showed no statistical difference between the experimental groups MTEP-2 M, BV45S5, and clot control in the two periods evaluated (p > 0.05). Conclusion The method used in this study was able to prepare macrosphere bioglass, and this material seems to be a promis- ing biomaterial to improve bone tissue regeneration.