Synthesis of polymerizable quaternary thiazole salts and their application as antibacterial agents for dental resin

Abstract

For the purpose of endowing dental resin with antibacterial activity without impairing physicochemical properties, polymerizable quaternarized thiazole salts (QAMEMT-x) with different alkyl chain length (12, 14, and 16) were synthesized and characterized by FT-IR and 1H-NMR spectra. After adding 5 wt% of QAMEMT-x into Bis-GMA/TEGDMA (50/50, wt./wt.) dental resin, double bond conversion (DC), volumetric shrinkage (VS), flexural strength (FS) and modulus (FM), water sorption (WS) and solubility (SL), and antibacterial activity against Streptococcus mutans (S. mutans) of obtained resin systems were investigated. The results showed that 5 wt% of QAMEMT-x had no influence on DC, FS, FM, WS, and SL (α > 0.05), while could reduce VS of dental resin (α < 0.05). Cured resins with 5 wt% of QAMEMT-x all showed antibacterial activity against S. mutans, and QAMEMT-16 could endow cured resin with the strongest antibacterial activity which showed an antibacterial efficiency of more than 99%.