The local application of a 1% simvastatin gel improves bone regeneration in osteoporotic mandibular defects: a rat model study.

Background: The purpose of this study is to evaluate the effectiveness of simvastatin in the bone formation of osteoporotic mandible in the rat model. Methods and materials: Eight Wistar male rats at the age of 6 months, with a weighted average of 250-300 grams, were purchased from the Atomic Energy Authority in Damascus (Syria). Osteoporosis was induced through bilateral orchiectomy, a procedure that involves the removal of the testes, under anesthesia with a combination of ketamine and xylazine. The lateral mandibular portion was selected to create a physiologically critical bone defect. In each rat, two adjacent defects were created in the mandible, and simvastatin gel 1% was applied to one side of them. The rats were euthanized over the first 3 months, and the defective portions of the mandible were processed for histological analysis of formed bone. Results: The study used Allen's scoring system to measure the amount of new bone formed in the defects treated with simvastatin compared to untreated defects. During the first and second months, the simvastatin-treated defects showed significantly higher bone formation than the untreated defects (P < 0.05), indicating that simvastatin had a positive impact on bone healing in the early stages. However, by the third month, this difference disappeared (P > 0.05), suggesting that simvastatin's effect on bone formation was strongest early on and did not provide additional benefits over time. Conclusions: Our findings suggest that local application of simvastatin (1% gel) has favorable effects on bone formation in osteoporotic mandibular rats.