Antifungal Resistance of Candidal Biofilms Formed on Denture Acrylic in vitro

• Published in: Journal of dental research 2001-03, Vol.80 (3), p.903-908
• Main Authors: Chandra, J., Mukherjee, P.K., Leidich, S.D., Faddoul, F.F., Hoyer, L.L., Douglas, L.J., Ghannoum, M.A.
• Format: Article
• Language: English
• Subjects: Acrylic Resins; Amphotericin B - administration & dosage; Amphotericin B - pharmacology; Anti-Infective Agents, Local - administration & dosage; Anti-Infective Agents, Local - pharmacology; Antifungal Agents - administration & dosage; Antifungal Agents - pharmacology; Biofilms - drug effects; Candida albicans - classification; Candida albicans - drug effects; Candidiasis, Oral - drug therapy; Candidiasis, Oral - microbiology; Chlorhexidine - administration & dosage; Chlorhexidine - pharmacology; Colony Count, Microbial; Dentistry; Denture Bases - microbiology; Dose-Response Relationship, Drug; Drug Resistance, Microbial; Fluconazole - administration & dosage; Fluconazole - pharmacology; Galactose - pharmacology; Glucose - pharmacology; Humans; Indicators and Reagents; Nystatin - administration & dosage; Nystatin - pharmacology; Polymethyl Methacrylate; Saliva - microbiology; Statistics as Topic; Stomatitis, Denture - drug therapy; Stomatitis, Denture - microbiology; Sucrose - pharmacology; Tetrazolium Salts; Time Factors
• ISSN: 0022-0345; 1544-0591
• DOI: 10.1177/00220345010800031101

Denture biofilms represent a protective reservoir for oral microbes. The study of the biology of Candida in these biofilms requires a reliable model. A reproducible model of C. albicans denture biofilm was developed and used to determine the susceptibility of two clinically relevant C. albicans isolates against 4 antifungals. C. albicans, growing as a biofilm, exhibited resistance to amphotericin B, nystatin, chlorhexidine, and fluconazole, with 50% reduction in metabolic activity (50% RMA) at concentrations of 8, 16, 128, and > 64 μg/mL, respectively. In contrast, planktonically cultured C. albicans were susceptible (50% RMA for the same antifungals was obtained at 0.25, 1.0, 4.0, and 0.5 μg/mL, respectively). In conclusion, results obtained by means of our biofilm model show that biofilm-associated C. albicans cells, compared with cells grown in planktonic form, are resistant to antifungals used to treat denture stomatitis.