Experimental study on the effects of a novel bone graft material based on poly(3-hydroxybutyrate) and simvastatin on bone formation

BACKGROUND: In surgical dentistry and maxillofacial surgery, no currently available bone graft material reliably provides predictable outcomes for the treatment of jawbone defects. Given the increasing number of patients with alveolar bone atrophy and post-traumatic jaw defects, the development of new materials with osteoinductive properties remains highly relevant, underscoring the importance of research in bone tissue engineering. AIM: To assess the osteoinductive potential of a novel bone graft material based on poly(3-hydroxybutyrate) loaded with simvastatin in an in vivo sheep model. METHODS: A single-center, prospective, comparative study was conducted between December 2022 and June 2023, involving 24 healthy sheep weighing 65–70 kg and aged 18–24 months. Strict inclusion and exclusion criteria ensured group homogeneity. Under general and local anesthesia, a lateral window approach to the maxillary sinus was performed to create a bony window for implantation. Group 1 received simvastatin-loaded poly(3-hydroxybutyrate) granules; group 2 received the same material without simvastatin. The primary outcome was the presence of morphological signs of osteoinduction, including the formation of new bone tissue. Secondary outcomes included morphometric assessment of structural bone parameters, such as the relative volume of newly formed bone and osteogenic activity. RESULTS: Assessments were performed at 3 and 6 months post-implantation. At 3 months, granules of the bone graft material in group 1 were surrounded by moderate connective tissue and multiple foci of active osteogenesis around the simvastatin-loaded granules. In group 2, connective tissue predominated around the implanted granules, with isolated osteogenic foci. At 6 months, group 1 exhibited reduced connective tissue, persistent osteogenic foci, and predominantly mature lamellar bone. Histomorphometric analysis revealed that the relative volume of newly formed bone in the simvastatin group was 34.5% at 3 months and 63.4% at 6 months, significantly exceeding that of the control group (21.4 and 36.8%, respectively). CONCLUSION: Simvastatin-loaded poly(3-hydroxybutyrate) granules significantly enhance bone formation. However, the long-term effects of simvastatin application require further investigation. © 2025 Elsevier B.V., All rights reserved.