title: Local antibiotic delivery in periodontitis: drug release and its effect on supragingival biofilms.
abstract: The effect of a drug-delivery system containing antibacterial metronidazole (MDZ) prescribed for periodontitis on supragingival biofilm was evaluated, and possible interference by this biofilm in the drug release profile was investigated. Streptococcus mutans biofilms were grown and exposed to a controlled-release formulation of MDZ or the same formulation without MDZ (vehicle control). Untreated biofilms were used as a negative control (NC). Biofilms and culture medium (containing detached cells) were collected 24, 48, 72, and 96 h after first exposure to treatments. The biomass of the MDZ group was lower than that of the NC group at all times. Although MDZ yielded low drug-release rates in the presence of the biofilm, it was sufficient for reducing viability for 24 h and affecting bacterial metabolism for 48 h. These results suggest that MDZ appears to destabilize supragingival biofilm. This biofilm may interfere with MDZ release from the formulation.
authors.affiliation: a Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto , University of São Paulo , São Paulo , Brazil.
authors.forename: A C S
authors.initials: AC
authors.lastname: Ré
authors.affiliation: b Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirão Preto , University of São Paulo , São Paulo , Brazil.
authors.forename: M P
authors.initials: MP
authors.lastname: Ferreira
authors.affiliation: b Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirão Preto , University of São Paulo , São Paulo , Brazil.
authors.forename: O
authors.initials: O
authors.lastname: Freitas
authors.affiliation: a Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto , University of São Paulo , São Paulo , Brazil.
authors.forename: C P
authors.initials: CP
authors.lastname: Aires
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D018441:Biofilms / Q000187:drug effects*; D016503:Drug Delivery Systems / Q000379:methods*; D065546:Drug Liberation; D006801:Humans; D008795:Metronidazole / Q000008:administration & dosage* / Q000494:pharmacology / Q000627:therapeutic use; D008954:Models, Biological; D010518:Periodontitis / Q000188:drug therapy / Q000382:microbiology*; D013295:Streptococcus mutans / Q000187:drug effects* / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D008795:Metronidazole
keywords: Streptococcus mutans; Supragingival biofilm; controlled delivery system; metronidazole