Repair of surgical bone defects grafted with hydroxylapatite + β-TCP combined with hyaluronic acid and collagen membrane in rabbits: A histological study

OBJECTIVES: This study aimed to assess the repair of bone defects with or without grafts using biphasic synthetic micro-granular hyaluronic acid (HA) with β-TCP and bovine type I collagen (Osteon II Collagen) with or without either hyaluronic acid or a collagen membrane in surgically created bone defects in the tibia of rabbits. METHODS: Fifteen male rabbits were divided into 3 groups, each with 5 rabbits. Two bone defects were made in each tibia. In the right tibia, the defects were either filled with clot as a control or grafted with Osteon II Collagen and hyaluronic acid. In the left tibia, the other two defects were filled with Osteon II Collagen alone or with Osteon II Collagen and a collagen membrane. The specimens were observed one, two, and four weeks after surgery. Histological examinations were used to evaluate the degree of healing according to the amount of newly formed bone. RESULTS: The combination of the bone grafting biomaterial with hyaluronic acid was found to develop into the most advanced stages of the bone repair process at the second and fourth week only (p ≤ 0.05), compared to the biomaterial with a collagen membrane, as well as the other groups. On the other hand, the biomaterial in combination with a collagen membrane showed significantly more bone formation than the biomaterial alone or the control group by the fourth week. CONCLUSIONS: The local application of hyaluronic acid and collagen membranes made a greater contribution to the bone repair process in the tibia of rabbits than the bone graft substitute (Osteon II Collagen) alone.