title: Immobilization of octadecyl ammonium chloride on the surface of titanium and its effect on microbial colonization in vitro.
abstract: The aim of our study was twofold: to immobilize an organosilicon quaternary ammonium salt (3-(trimethoxysilyl)-propyldimethyl-octadecyl ammonium chloride, Si-QAC) on the surface of pure titanium and to investigate the antimicrobial activity of Si-QAC-immobilized titanium against microbial adherence and biofilm formation. The results of ToF-SIMS analysis of Si-QAC-titanium suggested the possibility of immobilizing Si-QAC on titanium surface through Ti-O-Si coupling, and that Si-QAC treatment significantly reduced both the adherence and colonization of Candida albicans and Streptococcus mutans isolates. The antimicrobial activity was achieved through at least two mechanisms: the first was attributed to the octadecyl alkyl chain which inhibited initial adherence, and the second was attributed to the quaternary ammonium salt which killed initial adherent cells as well as retarded or inhibited subsequent microbial growth. Further, thermocycling did not significantly reduce the antimicrobial activity of Si-QAC-titanium, and no significant cytotoxicity of Si-QAC-titanium was observed in either cell viability test or proinflammatory cytokine production test using human gingival fibroblasts. These results, taken together, favorably suggested that Si-QAC treatment would be a helpful means to inhibit dental plaque or denture plaque formation.
authors.affiliation: Department of Medical Design & Engineering, Institute of Oral Health Science, Faculty of Dentistry, Hiroshima University, Minami-ku, Japan. hirocky@hiroshima-u.ac.jp
authors.forename: Hiroki
authors.initials: H
authors.lastname: Nikawa
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Ishida
authors.forename: Taizo
authors.initials: T
authors.lastname: Hamada
authors.forename: Takahiro
authors.initials: T
authors.lastname: Satoda
authors.forename: Takeshi
authors.initials: T
authors.lastname: Murayama
authors.forename: Toshinobu
authors.initials: T
authors.lastname: Takemoto
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Tamamoto
authors.forename: Hideaki
authors.initials: H
authors.lastname: Tajima
authors.forename: Saiji
authors.initials: S
authors.lastname: Shimoe
authors.forename: Hitomi
authors.initials: H
authors.lastname: Fujimoto
authors.forename: Seicho
authors.initials: S
authors.lastname: Makihira
mesh_terms: D000704:Analysis of Variance; D000891:Anti-Infective Agents, Local / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity; D001422:Bacterial Adhesion / Q000187:drug effects; D018441:Biofilms / Q000187:drug effects*; D002175:Candida / Q000187:drug effects; D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D015169:Colony Count, Microbial; D005347:Fibroblasts / Q000187:drug effects; D005881:Gingiva / Q000166:cytology / Q000187:drug effects; D006801:Humans; D050296:Microbial Viability / Q000187:drug effects; D017646:Organosilicon Compounds / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity; D000644:Quaternary Ammonium Compounds / Q000737:chemistry* / Q000494:pharmacology* / Q000633:toxicity; D018629:Spectrometry, Mass, Secondary Ion / Q000379:methods; D018709:Statistics, Nonparametric; D013295:Streptococcus mutans / Q000187:drug effects; D014025:Titanium / Q000737:chemistry*; D017155:Wettability
chemical_list: D000891:Anti-Infective Agents, Local; D017646:Organosilicon Compounds; D000644:Quaternary Ammonium Compounds; C018408:3-(trimethoxysilyl)propyldimethyloctadecylammonium; D014025:Titanium