Background: Enhancement of the bone regenerative capacity of the bone substitutes could
be achieved by incorporating bioactive agents such as proteins, and different drugs. Simvastatin, an
inhibitor of cholesterol synthesis, stimulates bone formation by enhancing the expression of Bone
Morphogenetic Protein-2 (BMP-2) in osteoblasts.
Objective: The objective of the study is to evaluate bone regeneration following simvastatin loaded
nano-hydroxyapatite scaffold in the bone defect created on the femoral condyle of rabbits.
Methods: Twelve adult, New Zealand white rabbits were used in the study. Twenty-four defects of size
5x8 mm were created on the lateral aspect of the femoral condyle. The defects were filled with either
Nano-Hydroxyapatite (nHA) particles alone or nHA with Simvastatin (SIM). The condyles were retrieved
after 8 weeks and analyzed using micro CT and histology.
Results: The Bone Mineral Density (BMD) was significantly higher for the defects filled with SIM
loaded nHA compared to the nHA site. Micro CT showed a significantly higher bone volume in the
defects filled with Simvastatin loaded site compared to the control site. Quantitative analysis of the
histologic sections also showed significantly higher bone volume in the defects filled with SIM loaded
nHA (57.2±4.8) compared to nHA alone (50.1±5.5).
Conclusion: Based on the results, it can be concluded that local delivery of simvastatin enhanced the
bone regeneration in rabbit femoral condyle. Simvastatin could be used as an activator to enhance bone
regeneration in bone defects along with hydroxyapatite ceramics.