title: Antibacterial activity of a modified unfilled resin containing a novel polymerizable quaternary ammonium salt MAE-HB.
abstract: Resins with strong and long-lasting antibacterial properties are critical for the prevention of secondary dental caries. In this study, we evaluated the antibacterial effect and the underlying mechanism of action of an unfilled resin incorporating 2-methacryloxylethyl hexadecyl methyl ammonium bromide (MAE-HB) against Streptococcus mutans UA159 (S. mutans UA159). MAE-HB was added into unfilled resin at 10 mass%, and unfilled resin without MAE-HB served as the control. Bacterial growth was inhibited on 10%-MAE-HB unfilled resin compared with the control at 1 d, 7 d, 30 d, or 180 d (P < 0.05). The growth inhibitory effect was independent of the incubation time (P > 0.05). No significant differences in the antibacterial activities of eluents from control versus 10%-MAE-HB unfilled resins were observed at any time point (P > 0.05). The number of bacteria attached to 10%-MAE-HB unfilled resin was considerably lower than that to control. Fe-SEM and CLSM showed that 10%-MAE-HB unfilled resin disturbed the integrity of bacterial cells. Expression of the bacterial glucosyltransferases, gtfB and gtfC, was lower on 10%-MAE-HB unfilled resin compared to that on control (P < 0.05). These data indicate that incorporation of MAE-HB confers unfilled resin with strong and long-lasting antibacterial effects against S. mutans.
authors.affiliation: State Key Laboratory of Military Stomatology &National Clinical Research Centre for Oral Diseases &Shaanxi International Joint Research Center for Oral Diseases, Department of General Dentistry and Emergency, School of Stomatology, Fourth Military Medical University, Xi'an, Shaanxi, 710032, P. R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Military Stomatology &National Clinical Research Centre for Oral Diseases &Shaanxi key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, P. R. China.
authors.forename: Fan
authors.initials: F
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Military Stomatology &National Clinical Research Centre for Oral Diseases &Shaanxi Engineering Research Center for Dental Materials and Advanced Manufacture, Department of VIP Dental Care, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, P. R. China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Military Stomatology &National Clinical Research Centre for Oral Diseases &Shaanxi key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, P. R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Dong
authors.affiliation: State Key Laboratory of Military Stomatology &National Clinical Research Centre for Oral Diseases &Shaanxi key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, P. R. China.
authors.forename: Ping-Ting
authors.initials: PT
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Military Stomatology &National Clinical Research Centre for Oral Diseases &Shaanxi key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, P. R. China.
authors.forename: Hao-Han
authors.initials: HH
authors.lastname: Yu
authors.affiliation: Department of Stomatology, Kunming General Hospital of PLA, Kunming, 650032, P. R. China.
authors.forename: Yu-Hong
authors.initials: YH
authors.lastname: Xiao
authors.affiliation: State Key Laboratory of Military Stomatology &National Clinical Research Centre for Oral Diseases &Shaanxi key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, P. R. China.
authors.forename: Zhi-Guo
authors.initials: ZG
authors.lastname: Chai
authors.affiliation: School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China.
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Xing
authors.affiliation: State Key Laboratory of Military Stomatology &National Clinical Research Centre for Oral Diseases &Shaanxi key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, 710032, P. R. China.
authors.forename: Ji-Hua
authors.initials: JH
authors.lastname: Chen