title: Efficacy of denture cleansers on Candida spp. biofilm formed on polyamide and polymethyl methacrylate resins.
abstract: BACKGROUND
  Although new materials have emerged as options to fabricate removable dental prostheses, the development of Candida biofilms on these materials and the effectiveness of methods to control these pathogenic biofilms are poorly understood.
  
  
  OBJECTIVE
  The purpose of this study was to evaluate the efficacy of denture cleansers on Candida single- and dual-species biofilms formed on polyamide resin.
  
  
  METHODS
  Polymethyl methacrylate (PMMA) resin (Acron MC) and polyamide resin (Flexite M.P.) specimens (n=116) were prepared, and their surface roughness was standardized (0.34 ±0.02 μm). Surface free energy (SFE) was measured for some specimens (n=20 per resin), while the remainder were randomly divided by lottery into 24 groups (n=8) for biofilm assay. C. albicans and/or C. glabrata biofilm was formed for 72 hours, and then specimens were treated with an enzymatic cleanser solution (Polident 3 Minutes), a cleanser solution (Corega Tabs), or 0.5% sodium hypochlorite (NaOCl) solution. Water served as the negative control. Remaining adherent microorganisms were removed from the treated specimens by ultrasonic waves, and colony-forming units (CFU) of each microorganism were calculated. SFE data were analyzed by 1-way ANOVA, and Candida species data were analyzed by 3-way ANOVA followed by the Tukey-Kramer test (P=.05).
  
  
  RESULTS
  All tested biofilms displayed significantly higher growth on polyamide resin (P<.001), which presented the lowest SFE. Denture cleansers significantly decreased Candida levels; however, the 0.5% NaOCl solution was the only effective cleanser. C. glabrata revealed significantly higher CFU counts under all experimental conditions (P<.001).
  
  
  CONCLUSIONS
  The highest Candida spp. biofilm growth was shown to occur on polyamide resin when compared with PMMA. Denture cleansers were able to remove Candida spp. biofilm formed on both denture base resins.
authors.affiliation: Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Piracicaba, São Paulo, Brazil.
authors.forename: Frederico Silva
authors.initials: FS
authors.lastname: de Freitas Fernandes
authors.forename: Tatiana
authors.initials: T
authors.lastname: Pereira-Cenci
authors.forename: Wander Jose
authors.initials: WJ
authors.lastname: da Silva
authors.forename: Antonio Pedro Ricomini
authors.initials: AP
authors.lastname: Filho
authors.forename: Fabiana Gouveia
authors.initials: FG
authors.lastname: Straioto
authors.forename: Altair Antoninha
authors.initials: AA
authors.lastname: Del Bel Cury
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D001881:Borates / Q000494:pharmacology; D002175:Candida / Q000187:drug effects* / Q000502:physiology; D002176:Candida albicans / Q000187:drug effects / Q000502:physiology; D041221:Candida glabrata / Q000187:drug effects / Q000502:physiology; D015169:Colony Count, Microbial; D019551:Dental Disinfectants / Q000494:pharmacology; D003764:Dental Materials / Q000737:chemistry*; D003820:Denture Cleansers / Q000494:pharmacology*; D006801:Humans; D006813:Humidity; D008422:Materials Testing; D009172:Mycology / Q000379:methods; D009757:Nylons / Q000737:chemistry*; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D016037:Single-Blind Method; D012973:Sodium Hypochlorite / Q000494:pharmacology; D013431:Sulfates / Q000494:pharmacology; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D017155:Wettability
chemical_list: D000180:Acrylic Resins; D001881:Borates; D019551:Dental Disinfectants; D003764:Dental Materials; D003820:Denture Cleansers; D009757:Nylons; D013431:Sulfates; C540407:corega tabs; C075051:Acron MC; C102654:Polident; D019904:Polymethyl Methacrylate; D012973:Sodium Hypochlorite