The influence of simvastatin on osteoblast functionality in the presence of titanium dioxide particles In-vitro.

Objective: Leaching of particles from dental titanium implant surfaces into preimplant microenvironment causes detrimental effects on bone cells. The current study investigated influence of simvastatin in mitigating adverse pro-inflammatory effects of titanium dioxide (TiO) micro (MP) and nano (NP) particles on hFOB 1.19 cells in vitro.

Design: Viability of hFOB 1.19 cells following exposure to varying concentrations of TiO MPs and NPs and simvastatin were measured by XTT assay. hFOB 1.19 cells were treated with 100 µg/mL of TiO MPs, 100 µg/mL of TiO NPs, 0.1 µM simvastatin, 100 µg/mL of TiO MPs+ 0.1 µM simvastatin and 100 µg/mL of TiO NPs+ 0.1 µM simvastatin. After 24 h, ROS was measured by flow cytometry. On day 14, real-time PCR analysis for pro-inflammatory cytokines and bone formation markers was done for TNFα, IL1β, osteocalcin, ALP, and Col1 markers; while ALP and RANKL/OPG ratio were determined by colorimetric and ELISA assays respectively. Further, mineralization study using Alizarin Red S staining (ARS) and calcium quantification were performed.

Results: Exposure of hFOB to TiO MPs and NPs generated ROS and reduced cell viability significantly, with upregulation of pro-inflammatory markers TNFα and IL1β and downregulation of bone formation markers OC and increased RANKL/OPG ratio and lowered degree of mineralization. Treatment with 0.1 µM of simvastatin treatment reversed the effects by mitigating oxidative stress, dampening pro-inflammatory markers, upregulation of bone formation markers, lowering RANKL/OPG ratio and increasing degree of mineralization.

Conclusion: Simvastatin possesses antioxidant, anti-inflammatory, and pro-osteogenic properties that may support bone healing around titanium implants.