Application of green mussel (Perna viridis) shells hydroxyapatite on osteocalcin levels and osteoblast cells in rabbit femur bone defect

BACKGROUND: Bovine hydroxyapatite (HA) used for bone grafts is relatively expensive, necessitating the development of alternative sources. Alternative HA materials derived from green mussel shells with smaller molecular sizes are inexpensive and abundantly available throughout Indonesian waters. The purpose of this study is to investigate the effect of green mussel shells HA on bone healing. METHODS: This post-test-only experimental research used male rabbits with femoral defects divided into three groups randomly: K (no treatment), P1 (bovine HA treatment), and P2 (green mussel shell HA treatment). The osteocalcin level was assessed biochemically while osteoblast cells were histopathologically at the second, fourth, and sixth weeks. Statistic tests were used to assess differences between groups and periods with statistical significance P<0.05. RESULTS: Nine rabbits in each group showed significant differences between groups K, P1, and P2 in term osteocalcin levels at week 2 (2.60, 4.53±0.12, 4.47±0.23; P=0.046), week 4 (5.13±0.12, 8.53±0.12, 7.47±0.12; P=0.025), and week 6 (8.20, 11.93±0.23, 10.93±0.31, P=0.023), while in term osteoblast cells only at week 6 (16.33±3.46, 26.10±3.52, 30.40±3.29; P=0.006). The osteocalcin level and osteoblast increased significantly between groups K and P1/P2 from the initial trial until the last week. Osteoblast cells in the groups P1/P2 increased significantly, especially at week 6. CONCLUSION: Green mussel shell HA has the biochemical effectiveness of osteocalcin and can increase osteoblast cells comparable to bovine HA, which can enhance bone healing.