The purpose of this study was to enhance the anti-bacterial adhesion effect against Streptococcus mutans (S. mutans) of fluorinated dimethacrylate (DF MA) based dental resin composites (DRCs) by using silicone dimethacrylate (SMA-MEO). The SMA-MEO was added into mixture of DFMA and tricyclo (5.2.1.0) decanedimethanol diacrylate (SR833s) (DFMA/SR833s = 50wt./50wt.) with mass ratios of 10wt% and 20wt% to form resin matrix both with fluorinated and silicon containing dimethacrylates, and then DRCs named DS+10%SMA-MEO and DS+20%SMA-MEO were prepared by mixing the resin matrix with silaned BaAlSiO2 filler particles at a mass ratio of 30wt./70wt. Double bond conversion, volumetric shrinkage and shrinkage stress, flexural strength and modulus, water sorption and solubility, contact angle and surface free energy, anti-bacterial adhesion effect against Streptococcus mutans (S. mutans), and cytotoxicity of prepared DRCs were investigated according to standard or referenced methods. Fluorinated dimethacrylate (DFMA) based DRC named DS and 2,2-bis[4-(2-hydroxy-3-methacryloy-loxypropyl)-phenyl]propane (Bis-GMA) based DRC named BT were used as controls. Adding SMA-MEO into DFMA based DRC could lead to higher double bond conversion (p<0.05), higher hydrophobicity (p<0.05), and lower surface free energy (p<0.05). Only DS+10%SMA-MEO had better anti-bacterial adhesion effect against S. mutans than DS (p<0.05). The SMA-MEO had no influence on volumetric shrinkage, shrinkage stress, flexural modulus, water sorption and solubility of DRC (p>0.05), but could reduce flexural strength of dry DRC (p<0.05). After water immersion, SMA-MEO containing DRCs had comparable flexural strength as DS (p>0.05). Compared with BT, DS and SMA-MEO containing DRCs had better or comparable physicochemical properties, and lower amount of adherent S. mutans. All of DRCs had comparable cytotoxicity (p>0.05). DRCs with both DFMA and SMA-MEO could have better anti-bacterial adhesion effect against S. mutans than DRC only with DFMA due to increased hydrophobicity and decreased Surface free energy, and the optimal mass fraction of SMA-MEO in DFMA based resin matrix was 10wt%.
Read full abstract