Injectable chitosan/β-glycerophosphate hydrogels with sustained release of BMP-7 and ornidazole in periodontal wound healing of class III furcation defects.

The aim of this study was to determine the effect of bone morphogenetic protein-7 (BMP-7) and ornidazole (ORN) loaded Chitosan/β-glycerophosphate (CS/β-GP) thermosensitive hydrogels on periodontal regeneration. CS/β-GP hydrogels with and without BMP-7 and ORN were compared with respect to physicochemical properties, release kinetics, and antimicrobial activity in vitro, and periodontal regeneration properties in class III furcation defects in beagles via radiography, histology including immunohistochemical staining of osteoblasts and osteoclasts, and histometric analysis. CS/β-GP hydrogels with and without BMP-7 and ORN had comparable physicochemical properties and gelation kinetics. Release kinetics showed that the hydrogels were capable of stable and sustained release of BMP-7 and ORN. The hydrogels loaded with ORN exhibited obvious antimicrobial activity against P. gingivalis. Histometric analysis quantitatively showed significantly more new bone and cementum, and less connective tissue in defects implanted with BMP-7 loaded hydrogels compared with hydrogels without BMP-7. The number of osteoclasts reduced significantly in the CS/BMP-7/ORN and CS/BMP-7 groups, while the number of osteoblasts increased significantly in these groups. Our findings showed that BMP-7 and ORN conferred additional advantages to the CS/β-GP hydrogel in periodontal regeneration and suggest potential consideration of this approach for periodontal therapy.