Introduction: Growth factors and others molecules with osteoinductive capacity could be considered biomaterials with an important role in the biological process of healing in the human body. These properties could be potentially employed to enhance bone healing. Platelet rich plasma and growth factors alone were studied in an experimental bone defect model in this PhD Thesis. Material and method: A prospective, comparative bilateral and controlled experimental study was performed. A bone cavitary defect of diameter 6 mm. in the proximal tibial metaphyseal and a 6 mm diaphysal fibula defect was made on 30 New Zealand white rabbits. The animals were divided in two groups of 15 rabbits that received, as treatment of the defect, platelet rich plasma (PRP) or platelet poor plasma (ppp) in the right tibia and fibula. The left tibia and fibula were untreated as a control group. The results were evaluated with a radiological, CTS-can and histological studies at 8, 12 and 16 weeks. Results: The 3D images from CT-scan reconstruction, bone mineral density (BMD) and qualitative histological studies demonstrated an improvement in the platelet poor plasma group (ppp) without statistically significant differences. The bone regeneration was obtained from a membranous process  without encondral reaction. The statistical study of different variables in relation to time and type of treatment revealed no significant differences (P < 0.05). Conclusion: Platelet rich plasma, easy to obtain, safe and autologous compound does not work as bone substitute with an osteoinduction capability in our bone defect experimental animal model.

Introduction: Growth factors and others molecules with osteoinductive capacity could be considered biomaterials with an important role in the biological process of healing in the human body. These properties could be potentially employed to enhance bone healing. Platelet rich plasma and growth factors alone were studied in an experimental bone defect model in this PhD Thesis. Material and method: A prospective, comparative bilateral and controlled experimental study was performed. A bone cavitary defect of diameter 6 mm. in the proximal tibial metaphyseal and a 6 mm diaphysal fibula defect was made on 30 New Zealand white rabbits. The animals were divided in two groups of 15 rabbits that received, as treatment of the defect, platelet rich plasma (PRP) or platelet poor plasma (ppp) in the right tibia and fibula. The left tibia and fibula were untreated as a control group. The results were evaluated with a radiological, CTS-can and histological studies at 8, 12 and 16 weeks. Results: The 3D images from CT-scan reconstruction, bone mineral density (BMD) and qualitative histological studies demonstrated an improvement in the platelet poor plasma group (ppp) without statistically significant differences. The bone regeneration was obtained from a membranous process  without encondral reaction. The statistical study of different variables in relation to time and type of treatment revealed no significant differences (P < 0.05). Conclusion: Platelet rich plasma, easy to obtain, safe and autologous compound does not work as bone substitute with an osteoinduction capability in our bone defect experimental animal model.