RESUMO
STATEMENT OF PROBLEM: 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. PURPOSE: The purpose of this study was to evaluate the efficacy of denture cleansers on Candida single- and dual-species biofilms formed on polyamide resin. MATERIAL AND 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.
Assuntos
Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Materiais Dentários/química , Higienizadores de Dentadura/farmacologia , Nylons/química , Polimetil Metacrilato/química , Resinas Acrílicas/química , Biofilmes/crescimento & desenvolvimento , Boratos/farmacologia , Candida/fisiologia , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Candida glabrata/efeitos dos fármacos , Candida glabrata/fisiologia , Contagem de Colônia Microbiana , Desinfetantes de Equipamento Odontológico/farmacologia , Humanos , Umidade , Teste de Materiais , Micologia/métodos , Método Simples-Cego , Hipoclorito de Sódio/farmacologia , Sulfatos/farmacologia , Propriedades de Superfície , Temperatura , Fatores de Tempo , MolhabilidadeRESUMO
PURPOSE: To evaluate the surface properties and Candida albicans adherence on two acrylic resins, one polymerized by long cycle and the other by short polymerization cycle, with added 2% PTFE (wt/wt) (experimental groups) or not added (control groups). METHODS: The specimens were divided into four groups (n = 10 per group): (1) acrylic resin polymerized by long cycle; (2) acrylic resin polymerized by long cycle with added 2% PTFE; (3) acrylic resin polymerized by short cycle; and (4) acrylic resin polymerized by short cycle with added 2% PTFE. After finishing and polishing, all specimens were assessed for their surface roughness (pm), contact angle (degree) and surface free energy (erg/cm 2) Saliva-coated specimens were submitted to the adherence assay with C. albicans (ATCC 90028). Adhered cells were detached from the acrylic resin surface by ultrasonic waves at 7 watts for 30 seconds in phosphate buffered saline solution (PBS). This cell solution was serially diluted in PBS and plated on Sabouraud agar. The results were expressed in colony forming units per surface area (CFU/mm2). The data was analyzed by two-way ANOVA. The significance limit was set at 5%. RESULTS: No statistical differences were found for roughness, contact angle and surface free energy. There was a reduction trend in C. albicans adherence in PTFE added to resins, but it was not statistically significant.