The biodegradable hydroxyapatite/ chitosan/ collagen composites of similar composition to the normal human bone were prepared as a biomimetic scaffold for bone replacement and regeneration.
Objectives: The aim of the present study was to evaluate the influence of these synthetic bone grafts on the inflammatory response and remodeling of connective tissue during wound-healing process.
Methods: Three sample types were developed- B1 (hydroxyapatite 0,25mm/ collagen 1%/ chitosan 0,5%), B2 (hydroxyapatite 0,50mm/ collagen 1%) and B3 (hydroxyapatite 0,25mm/ collagen 1%) and implanted subcutaneously in the dorsal lumbar region of 45 Wistar rats. Histomorphometric evaluation of capsule thickness, capsule quality, implant-tissue interface, infiltrate/ inflammation and cellular growth within implant was performed 3, 7 and 28 days post-operatively (n=5). Immunohistochemistry was performed for further characterization of the macrophages infiltrate. ANOVA and Student's t-test were used to test the difference between the experimental groups (p<0.05).
Results: Statistical analysis of the capsule thickness and capsule quality didn't show significant differences between the biomaterials and time of implantation. The biomaterial B1 showed significant difference in inflammatory cellular response than B2 and B3 at 7 days. A low ongoing foreign body reaction was observed in all biomaterials characterized by infiltration of few macrophages. A significant cellular growth within the B3 was observed at 28 days. Histological and immunohistochemical analysis suggested that the biomaterials were well tolerated with low inflammatory response.
Conclusion: The hydroxyapatite/ collagen/ chitosan biomaterials (B1, B2 and B3) showed good biocompatibility which makes them suitable candidates to design of bone replacement graft material.