Antibacterial Effect of Mineral Trioxide Aggregate Associated With Essential Oils

Objectives: The antibacterial property of Mineral Trioxide Aggregate (MTA) could be favored by addition of essential oils as Tea Tree Oil (TTO) and Farnesol (FAR). TTO is an essential oil, and farnesol is a sesquiterpene, both have antibacterial properties. The aim of this study was to evaluate the physicochemical and antibacterial properties of MTA associations: MTA/TTO 1%, MTA/TTO 2%, MTA/FAR 1% and MTA/FAR 2% compared to white MTA Angelus.
Methods: Physicochemical evaluations followed ISO and ADA specifications. Initial and final Setting Time (ST) were measured with Gilmore needles. Solubility was calculated by the weight loss after 7 and 30 days. The volume change was analyzed using Micro-CT after 7 and 30 days. Radiopacity was observed with X-rays of materials and aluminum scale. The antibiofilm activity was analyzed using the Crystal Violet (CV) assay. The biofilm biomass reduction of Enterococcus faecalis biofilm was observed after contact with tested materials. Direct Contact Test Modified (DCTM) was assessed after contact of materials with Entercoccus faecalis biofilm induced on bovine dentin. After plating, it was performed the Colony Forming Units per ml (CFUmL^-1). All data were submitted to ANOVA and Tukey tests, with 5% significance.
Results: All materials showed similar at solubility, volume change at 7 days, and radiopacity (p>0.05). Initial and final ST were lower for MTA and higher for farnesol associations (p>0.05). The Micro-CT analysis after 30 days, both associations at 2% improved volumetric change (p <0.05). The CV assay and DCTM showed MTA/FAR 1%, MTA/FAR 2% and MTA/TTO 2% were more effective against E. faecalis biofilm(p> 0.05).
Conclusions: Association of MTA with antimicrobial substances tea tree oil and farnesol improves its antimicrobial properties, with no change in some physicochemical properties. These associations have potential for alternative use to MTA, after biological assessments.