title: Antibacterial effect of bactericide immobilized in resin matrix.
abstract: OBJECTIVE
  Biomaterials with anti-microbial properties are highly desirable in the oral cavity. Ideally, bactericidal molecules should be immobilized within the biomaterial to avoid unwanted side-effects against surrounding tissues. They may then however loose much of their antibacterial efficiency. The aim of this study was to investigate how much antibacterial effect an immobilized bactericidal molecule still has against oral bacteria.
  
  
  METHODS
  Experimental resins containing 0, 1 and 3% cetylpyridinium chloride (CPC) were polymerized, and the bacteriostatic and bactericidal effects against Streptococcus mutans were determined. Adherent S. mutans on HAp was quantitatively determined using FE-SEM and living cells of S. mutans were quantified using real-time RT-PCR. The amount of CPC released from the 0%-, 1%- and 3%-CPC resin sample into water was spectrometrically quantified using a UV-vis recording spectrophotometer.
  
  
  RESULTS
  UV spectrometry revealed that less than 0.11 ppm of CPC was released from the resin into water for all specimens, which is lower than the minimal concentration generally needed to inhibit biofilm formation. Growth of S. mutans was significantly inhibited on the surface of the 3%-CPC-containing resin coating, although no inhibitory effect was observed on bacteria that were not in contact with its surface. When immersed in water, the antibacterial capability of 3%-CPC resin lasted for 7 days, as compared to resin that did not contain CPC.
  
  
  CONCLUSIONS
  These results demonstrated that the bactericidal molecule still possessed significant contact bacteriostatic activity when it was immobilized in the resin matrix.
authors.affiliation: Department of Pathophysiology-Periodontal Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, 2-5-1 Shikata-cho, Okayama 700-8525, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Namba
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Yoshida
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Nagaoka
authors.forename: Seisuke
authors.initials: S
authors.lastname: Takashima
authors.forename: Kaori
authors.initials: K
authors.lastname: Matsuura-Yoshimoto
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Maeda
authors.forename: Bart
authors.initials: B
authors.lastname: Van Meerbeek
authors.forename: Kazuomi
authors.initials: K
authors.lastname: Suzuki
authors.forename: Shogo
authors.initials: S
authors.lastname: Takashiba
mesh_terms: D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D001433:Bacteriolysis; D002594:Cetylpyridinium / Q000494:pharmacology*; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000032:analysis; D017886:Durapatite; D019279:Resin Cements / Q000737:chemistry*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013295:Streptococcus mutans / Q000187:drug effects*; D013499:Surface Properties
chemical_list: D000891:Anti-Infective Agents, Local; D004269:DNA, Bacterial; D019279:Resin Cements; D017886:Durapatite; D002594:Cetylpyridinium