Simvastatin Efficacy on Endodontic Biofilms: An In Vitro Study

Abstract

The outcome of endodontic therapy is directly related to the control of infection. The aim of the study was to evaluate in vitro the efficacy of Simvastatin (SIM) and diclofenac (DC) solutions on endodontic biofilms. Methods: Mature biofilms were grown on dentin specimens and put in contact with the solutions to determine their antibiofilm activity. To assess residual antimicrobial activity, the dentin samples were immersed for 5 min in the solutions before microbial infection for 3 weeks. The study groups were: (1) 8% SIM, (2) 4% SIM, (3) 4% DC, (4) 2.5% sodium hypochlorite (NaOCl), and (5) 0.9% saline solution (SS). Cell viability was evaluated by means of the adenosine triphosphate (ATP) assay and flow cytometry (FC). The data collected were analyzed with the ANOVA test using Welch’s correction followed by the Games–Howell test. The level of statistical significance was p < 0.05, and statistical analysis was performed using SPSS 23.0. Results: All study groups reduced the biofilms significantly with respect to the control. The highest reduction percentage was obtained by 2.5% NaOCl, followed by SIM 8% and 4%, without statistically significant differences. In terms of residual activity, the 4% DC solution obtained a higher percentage of dead cells. Conclusion: Solutions of 4% and 8% SIM, and 4% Diclofenac, show antimicrobial and residual activity against multispecies endodontic biofilms.