Physicochemical and biological evaluation of a triazine-methacrylate monomer into a dental resin

Abstract

This study aimed to (1) formulate blend resins with 2.5 or 5wt.% of the methacrylate monomer 1,3,5-triacryloylhexahydro-1,3,5-triazine (TAT), and (2) to evaluate the blend resins regarding the physicochemical and biological properties. The base resin was formulated mixing 60wt.% of bisphenol A glycol dimethacrylate and 40wt.% of triethylene glycol dimethacrylate with photoinitiator/co/initiator system. TAT was added at 2.5 (G2.5%) or 5 (G5%) wt.%, and a group without TAT was used as control (Gctrl). The resins were analyzed for degree of conversion (DC), Knoop hardness (KHN), softening in solvent (ΔKHN), ultimate tensile strength (UTS), contact angle, surface free energy (SFE), antibacterial activity against Streptococcus mutans biofilm formation, and cytotoxicity against human keratinocytes. There was no difference for the DC (p=0.676). The addition of TAT at 5wt.% induced higher KHN (p<0.001), higher resistance against softening in solvent (p<0.001), and higher UTS (p=0.04). There were no statistically significant differences for contact angle with water (p=0.106), α-bromonaphtalene (p=0.454), and SFE (p=0.172). The higher the TAT concentration, the higher the antibacterial activity (p<0.001). G2.5% showed no cytotoxicity compared to Gctrl (p>0.05), and G5% induced lower cell viability (p<0.05). The addition of 2.5wt.% of TAT is suitable for conveying antibacterial activity for dental resins without changing the physicochemical properties or impairing the cytotoxic effect. Methacrylate monomers that decrease bacterial viability and copolymerize with the resin matrix are exciting approaches to developing therapeutic materials. TAT showed promising properties to may hamper and prevent carious lesions when incorporated into dental materials. Further evaluations with higher cariogenic challenges will be carried to analyze the formulated materials.