Abstract
OBJECTIVE: To evaluate bioactivity and osteogenic potential of calcium silicate (CS)-doped iron oxide (Fe(2)O(3)) nanoparticles versus pure CS in the reconstruction of induced critical-sized mandibular defects. DESIGN: CS-doped Fe(2)O(3) was prepared; morphological and microstructure identification of nanoparticles were made. An in vivo randomised design was developed on 24 adult male dogs where four critical-sized mandibular defects were created in each dog. Bone defects were allocated into control, CS, CS-3% Fe(2)O(3) and CS-10% Fe(2)O(3) group. Dogs were euthanized at 1 and 3 months (12 dog/time) for histopathologic and histomorphometric evaluation. RESULTS: At three months, bone formation and maturation were evident where mean ± SD percent of mature bone was 2.66 ± 1.8, 9.9 ± 2.5, 22.9 ± 4.9, and 38.6 ± 8.1 in control, CS, CS-3% Fe(2)O(3), and CS-10% Fe(2)O(3) groups respectively. A high significant (P < 0.001) increase in area percent of mature bone was recorded in CS, CS-3% Fe(2)O(3), and CS- 10% Fe(2)O(3) groups compared to control group (73%, 88% and 93.3% respectively). Significant increase (P < 0.001) in area of mature bone was recorded in CS-3% Fe(2)O(3) and CS-10% Fe(2)O(3) groups compared to CS group. A significant increase (P < 0.001) in area of mature bone formation was detected in CS-10% Fe(2)O(3) group compared to other groups. CONCLUSION: CS-doped Fe(2)O(3) has good osteoconductive, biocompatible properties with promoted bone regeneration. Fe(2)O(3) has synergistic effect in combination with CS to promote bone formation. Increasing concentration of Fe(2)O(3) nanoparticles resulted in improved osteogenesis and maturation. Results suggests that the novel CS-Fe(2)O(3) alloplasts could be used for reconstruction of critical-sized bone defects.