ANTIMICROBIAL AND CYTOTOXIC ACTIVITY OF CARVACROL FOR DECONTAMINATION OF TITANIUM SURFACES

OBJECTIVES To evaluate the antimicrobial, antibiofilm and cytotoxic properties of Carvacrol on planktonic culture and mature biofilms of Porphyromonas gingivalis (Pg) and Fusobacterium nucleatum (Fn) on titanium surfaces sanded with TiO particles and their cytotoxicity on fibroblast cell line. METHODS The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (CMB) of Carvacrol in planktonic culture and biofilm developed in microtiter plate and evaluated by the Tetrazolium Salt (XTT) assay. The viability of monospecies and multispecies biofilms developed on titanium discs after application of Carvacrol (0.26% and 0.06%) and Chlorhexidine (CHX 0.2%) were quantified in colony forming units (CFU mL-1) and evaluated by Confocal Scanning Laser Microscopy (CLSM). The cytotoxicity of Carvacrol was evaluated on cell culture of fibroblasts. After 5 minutes, 1 and 24 hours contact with Carvacrol (0.26% and 0.06%) the results were evaluated by the colorimetric MTT (methyltetrazolium) assay. The results were compared using the Kruskal Wallis and Mann Whitney test and ANOVA and Tukey HSD tests, depending on the distribution, with a significance level of 5%. RESULTS The lowest concentration capable of inhibiting bacterial growth (MIC) were Carvacrol 0.007% and 0.002% respectively for Pg and Fn. CMB values were similar to MIC. The results obtained by the XTT assay showed antimicrobial activity at Carvacrol concentrations 0.03% for Pg and 0.06% for Fn. CFU mL-1 and CLSM showed monospecies and multispecies antibiofilm activity on titanium disks using Carvacrol 0.26% and 0.06% respectively. The cytotoxic evaluation (MTT) of Carvacrol on fibroblast cell culture showed results statistically similar to CHX 0.2%. CONCLUSION Carvacrol has antimicrobial properties and is effective on mature biofilms of Porphyromonas gingivalis and Fusobacterium nucleatum; formed on sandblasted titanium surfaces with TiO particles, involved in peri-implant disease and it shows Chlorhexidine-like cytotoxicity.