Effect of doxycycline-bioglass treatment on calvarial bone defect in rats: A histological study

Purpose: To evaluate the osteogenic properties of a bioglass-doxycycline complex for bone regeneration applications in calvarial bone defects in rats.Methods: Three critical-size bone defects were created in each of eight experimental rats using a trephine bur. The experimentally created defects were then filled with bioglass-doxycycline (BG-D group), bioglass alone (BG group), or left unfilled (control group). Four randomly selected rats weresacrificed after 4 weeks while the other four rats were sacrificed after 8 weeks. The amount of newly regenerated bone and the osteoblast and osteoclast counts were calculated using histological analysis.Results: Increase in the amount of regenerated bone was significant in the bioglass-doxycycline group at both 4 and 8 weeks (p < 0.05). Differences between the three groups in the mean number of osteoblasts were also significant at both 4 and 8 weeks (p < 0.05). Comparison of the three groupsrevealed significant increase in osteogenesis rate and considerable enhancement of the number of osteoblasts in both bioglass and bioglass-doxycycline groups (p < 0.05).Conclusion: The complex of doxycycline and bioglass increased the rate of osteogenesis and number of osteoblasts in rats but decreased the number of osteoclasts. Therefore, bioglass-doxycycline can be considered as a bone graft in bone regeneration for medical applications. Keywords: Bone, Regeneration, Osteoblasts, Osteoclasts, Osteogenesis, Bioglass, Doxycycline