Effectiveness of Nanosilver, Nanogold and their Combination on the Healing Potential of Critical Radial Bone Defects in Rats

A new composition of platelet-fibrin glue (FPG), gelatin (Gel), nanohydroxyapatite (nHA), silver nanoparticles (SNPs) and gold nanoparticles (GNPs) was synthesized and employed in preparation of hybrid scaffolds and was applied in bone tissue engineering in the surgically critical-sized bone defect in a rat model. Sixty bilateral radial bone defects were randomly divided into six groups including untreated defects, autograft and those treated with Gel/FPG/nHA containing scaffolds including nHA alone, nHA/SNPs, nHA/GNPs and nHA/SNPs/GNPs (n=10 in each group). The defects were assessed by radiography, histopathology, scanning electron microscopy and biomechanical testing. In comparison with the untreated defects, all the treated defects demonstrated significantly superior new bone formation, remodeling and bone tissue volume. Moreover, the defects treated with GNPs showed significantly higher ultimate strength, yield strength and stiffness. The nHA and nHA/SNPs moderately improved bone regeneration that were not close to the autograft in some parameters, whereas nHA/GNPs and nHA/SNPs/ GNPs significantly improved bone healing closely comparable with those of the autograft group in most parameters. In conclusion, although all the scaffolds had some beneficial effectiveness on bone regeneration, the scaffolds containing GNPs were more effective in improving the structural and functional properties of the newly formed bone and were more osteoinductive than other scaffolds and were comparable to the autograft. Therefore, the scaffolds including GNPs can be regarded as a promising option to be used in bone tissue engineering.