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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Anti-Bacterial Agents, Biofilms, Bioreactors, Cells, Cultured, Coated Materials, Biocompatible, Dental Caries, Dental Materials, Humans, Metal Nanoparticles, Methacrylates, Microbial Sensitivity Tests, Microbial Viability, Nanocomposites, Polysaccharides, Silver, Streptococcus mutans, Surface Properties.
user
Does silver-polysaccharide antimicrobial nanocomposite coating for methacrylic surfaces reduce Streptococcus mutans biofilm formation in vitro? Context: The aim of this study was to determine the in vitro microbiological performances of a lactose-modified chitosan (Chitlac) coating inside which silver nanoparticles were embedded (Chitlac-nAg) for BisGMA/TEGDMA methacrylic specimens. Different concentrations of nAg inside Chitlac coating were tested (1 mM, 2 mM, 5 mM). Specimen surface was analyzed by means of field-emission scanning electron microscopy (FEISEM) and energy-dispersive X-ray spectroscopy (EDS). A 48 h monospecific Streptococcus mutans biofilm was developed over the specimen surfaces using a modified drip-flow bioreactor; adherent viable biomass was assessed by MTT test and biofilm was imaged by confocal laser-scanning microscopy (CLSM). The presence of finely dispersed nanoparticles inside the Chitlac coating was confirmed by FEISEM and EDS analysis. All nanoparticles were embedded in the Chitlac coating layer. Chitlac-nAg coatings were able to significantly decrease biofilm formation depending on the nAg concentration, reaching a -80% viable biomass decrease when the 5 mM nAg-Chitlac group was confronted to non-coated control specimens. CLSM analysis did not provide evidence of a contact-killing activity, however the antibacterial Chitlac-nAg coating was able to alter biofilm morphology preventing the development of mature biofilm structures.
assistant
The microbiological model applied in this study helped in assessing the antibacterial properties of a coating designed for methacrylate surfaces. Final Decision: yes