title: Antibacterial effects of three experimental quaternary ammonium salt (QAS) monomers on bacteria associated with oral infections.
abstract: The aim of this study was to test the antibacterial effects of three experimental quaternary ammonium salt monomers in order to evaluate their potential applications as dental materials. In vitro susceptibility testing of the monomers was performed by the broth dilution method on bacteria associated with oral infections: Streptococcus mutans ATCC 25175, Actinomyces viscosus ATCC 15987, Staphylococcus aureus ATCC 29213 and Lactobacillus casei ATCC 393. The time-kill kinetics of the monomer with relatively higher antibacterial activity against S. mutans were also investigated. It was found that all the tested bacteria strains were susceptible to the three monomers, among which methacryloxylethyl cetyl ammonium chloride (DMAE-CB) exhibited the lowest minimal inhibitory concentrations, ranging from 1.2 to 4.8 microg/ml. The time-kill curve showed that DMAE-CB achieved 99.44% killing at 19.2 microg/ml (4 times the minimal bactericidal concentration) against S. mutans after 1 min and 100% killing within 10 min of contact. This result indicates that the quaternary ammonium salt monomer DMAE-CB may be a candidate antibacterial agent for incorporation into dental restorative materials.
authors.affiliation: Department of Prosthodontics, School of Stomatology, Fourth Military Medical University, Xi'an, China.
authors.forename: Yu-Hong
authors.initials: YH
authors.lastname: Xiao
authors.forename: Ji-Hua
authors.initials: JH
authors.lastname: Chen
authors.forename: Ming
authors.initials: M
authors.lastname: Fang
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Xing
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.forename: Ying-Jie
authors.initials: YJ
authors.lastname: Wang
authors.forename: Fang
authors.initials: F
authors.lastname: Li
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D001421:Bacteria, Anaerobic / Q000187:drug effects*; D015169:Colony Count, Microbial; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D009059:Mouth Diseases / Q000382:microbiology; D000644:Quaternary Ammonium Compounds / Q000737:chemistry / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D000644:Quaternary Ammonium Compounds