Purpose: The purpose of this study was to evaluate whether the level of bone formation differed according to the ratio of the HA and β-TCP components.
Materials and methods: In the cranial area of 60 rats, bone grafts were performed using four bone graft materials with different ratios of HA/β-TCP: (1) unfilled defect, (2) HA (100 %), (3) HA (70 %)/β-TCP (30 %), (4) HA (30 %)/β-TCP (70 %), and (5) β-TCP (100 %). The rats were sacrificed after 4 weeks or 8 weeks, and the bone formation area was evaluated under a light microscope.
Results: In the 4-week groups, the bone formation area in the rats grafted with β-TCP (100 %) was 0.75±0.21 mm2, and slightly larger bone formation areas were observed than in other groups; nonetheless, these values were not statistically significant in comparison with the other groups. Similarly, significant differences were not shown among any other groups. In the 8-week groups, in the rats grafted with HA (100 %) and HA (30 %)/β-TCP (70 %), bone formation was observed to be 2.60±1.03 mm2 and 2.56±0.93 mm2, respectively. Thus, more abundant bone formation was observed in these two groups than in the other three groups, and this difference was statistically significant.
Conclusion: Based on the results, the amount of new bone formation is greatest when bone grafts are performed using the graft materials HA 100 % or HA (30 %)/β-TCP (70 %); thus, good bone formation outcomes are expected when using these materials in humans.