Simvastatin in polymer bioscaffold for bone regeneration. An in vitro and in vivo analysis

OBJECTIVE: The study aimed to fabricate and test the biocompatibility of a polylactic-co-glycolic acid (PLGA) based guided tissue regeneration membrane impregnated with 'simvastatin' to promote sustained drug delivery near osseous defects and evaluate the regenerative potential of the membrane histologically. MATERIALS AND METHODS: We tested the mechanical properties and cytotoxicity of an indigenously fabricated PLGA membrane incorporated with simvastatin (1 mg/cm2). An animal study evaluated the regenerative potential of the membrane. Twenty-four adult Wistar rats, approximately 175 g in weight, were used in this study. The rats were divided randomly into four groups based on the postoperative healing periods into ten days, 1, 3, and 6 months. Within each time group, six rats were divided into three subgroups: Subgroup A - sham surgery controls; Subgroup B - PLGA without Simvastatin; Subgroup C - PLGA with simvastatin tests. The radiographic examination intervals were ten days, 1 and 3 months, while the histological assessment was around 1, 3, and 6 months. RESULTS: Simvastatin content was distributed uniformly in all the prepared membranes and was equivalent to 1 mg/cm2. 100 mg PLGA membrane with simvastatin demonstrated uniform drug release over time, excellent mechanical properties, and biocompatibility. The rat models in Subgroup C had better bone tissue formation radiographically and histologically. CONCLUSION: The study suggested that 'PLGA with Simvastatin' has the requisite properties to serve as a third-generation barrier membrane with the potential for local drug delivery.