title: Development of a new model system to study microbial colonization on dentures.
abstract: OBJECTIVE
  Dentures are often colonized with a variety of microorganisms, including Candida albicans, that contribute to denture stomatitis. Several in vitro models have been previously established to study denture-related microbial colonization and evaluate treatment efficacy of denture cleansers; however, those models typically fail to appreciate the complex topology and heterogeneity of denture surfaces and lack effective ways to accurately measure microbial colonization. The purpose of this study was to study microbial colonization with a new model system based on real dentures, to more realistically mimic in vivo conditions.
  
  
  METHODS
  Scanning electron microscopy was used to observe topological structures among surfaces from different parts of the denture. Employing C. albicans as a model microorganism, we established microbial colonization on different denture surfaces. Moreover, we applied a modified MTT (3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide) colorimetric assay to quantify C. albicans colonization on dentures without the necessity of biofilm removal and to evaluate treatment efficacy of denture cleansers.
  
  
  RESULTS
  There were significant variations in topological structures among surfaces from different parts of the denture, with the unpolished side having the highest amounts of indentations and pores. The distinct denture surfaces support microbial colonization differently, with the unpolished side containing the highest level of microbial colonization and biofilm formation. Furthermore, the modified MTT colorimetric assay proved to be an accurate assay to measure biofilm formation on dentures and evaluate treatment efficacy of denture cleansers.
  
  
  CONCLUSIONS
  This new denture model system in conjunction with the MTT colorimetric assay is a valuable tool to study denture-related microbiology and treatment approaches.
authors.affiliation: West China School of Stomatology, Sichuan University, Chengdu, China.
authors.forename: Tingxi
authors.initials: T
authors.lastname: Wu
authors.forename: Wei
authors.initials: W
authors.lastname: Hu
authors.forename: Lihong
authors.initials: L
authors.lastname: Guo
authors.forename: Marybeth
authors.initials: M
authors.lastname: Finnegan
authors.forename: David J
authors.initials: DJ
authors.lastname: Bradshaw
authors.forename: Paul
authors.initials: P
authors.lastname: Webster
authors.forename: Zvi G
authors.initials: ZG
authors.lastname: Loewy
authors.forename: Xuedong
authors.initials: X
authors.lastname: Zhou
authors.forename: Wenyuan
authors.initials: W
authors.lastname: Shi
authors.forename: Renate
authors.initials: R
authors.lastname: Lux
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D000935:Antifungal Agents / Q000494:pharmacology; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development*; D001881:Borates / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D003124:Colorimetry / Q000379:methods; D004396:Coloring Agents; D003764:Dental Materials / Q000737:chemistry; D003819:Denture Bases / Q000382:microbiology; D003820:Denture Cleansers / Q000494:pharmacology; D003778:Dentures / Q000382:microbiology*; D005840:Gentian Violet; D006801:Humans; D050296:Microbial Viability / Q000187:drug effects; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D011137:Polystyrenes / Q000737:chemistry; D016062:Porosity; D013431:Sulfates / Q000494:pharmacology; D013499:Surface Properties; D013778:Tetrazolium Salts; D013844:Thiazoles; D014093:Tooth, Artificial / Q000382:microbiology
chemical_list: D000180:Acrylic Resins; D000935:Antifungal Agents; D001881:Borates; D004396:Coloring Agents; D003764:Dental Materials; D003820:Denture Cleansers; D011137:Polystyrenes; D013431:Sulfates; D013778:Tetrazolium Salts; D013844:Thiazoles; C102654:Polident; C022616:thiazolyl blue; D005840:Gentian Violet
keywords: Candida; Denture; MTT; antimicrobial treatment; biofilm