In Vitro Toxicological Assessment of an Injectable Simvastatin-Hydroxyapatite-Carbopol Scaffold: A Concentration-Dependent Biocompatibility Study for Maxillofacial Applications

Abstract

Introduction: The local delivery of simvastatin (SIM) from injectable scaffolds is a promising strategy for enhancing bone regeneration. Establishing a safe and effective therapeutic window is critical, as high concentrations of statins may induce cytotoxic effects.

Methods: Injectable hydroxyapatite-carbopol scaffolds incorporating 0.25 mg, 0.5 mg, and 0.75 mg of simvastatin per unit dose were fabricated alongside a control. Physicochemical characterization was performed using FTIR and SEM. Cytotoxicity on L929 fibroblasts was assessed via the MTT assay after 48 and 72 h.

Results: All scaffolds maintained integrity with porous morphology. FTIR confirmed successful incorporation of simvastatin. MTT assay results showed >90% cell viability across concentrations. Notably, the 0.75 mg SIM group promoted proliferation (~110% viability at 72 h).

Conclusion: The injectable SIM-HA-Carbopol scaffold exhibits excellent in vitro biocompatibility within the tested concentration range. The 0.75 mg dose appears optimal, combining safety with enhanced bioactivity.