Comparing the osteogenic capacities of bone substitutes: Hydroxyapatite, high-density porous polyethylene, and bone collagen: A biochemical and histological analysis

Several inorganic materials have been shown previously to hold some osteogenic capacity. The purpose of this study is to compare the bone-forming abilities of hydroxyapatite ceramic, high-density porous polyethylene, and bone collagen within the periosteal island flap of rabbit tibia using histological and biochemical analysis. With this goal, four discrete experimental groups were formed, each comprising 22 New Zealand male rabbits. A sac was created on each rabbit tibial periosteum flap in each of the groups, and each of the previously mentioned materials was placed within this sac separately. One of these groups was thought as a control group without any material being placed inside the periosteal sac. Biopsies were taken at weeks 1, 2, 4, and 8 for biochemical analysis and at weeks 2 and 8 for histological evaluation. Neoosteogenesis was evaluated quantitatively by determination of alkaline phosphatase and osteocalcin levels biochemically as well as by the percentage of new bone formation inside the periosteal sac histologically. Results show statistically that the osteogenic effect of high-density porous polyethylene is greater than that of the other materials used in this study (P < 0.05).