Effect of surface roughness on the hydrophobicity of a denture-base acrylic resin and Candida albicans colonization

Journal of Investigative and Clinical Dentistry Volume: 7 Issue: 2 Pages: 141-148 Published: 2016

Scanning electron microscopy images (91000 magnification) showing the denture-base acrylic resin surfaces (left), C. albicans adhesion (center), and C. albicans biofilm formation (right). From top to bottom: representative images of typical fields of view for the smoothest surface (group roughness average [Ra] 0.05), intermediate roughness (group Ra 0.4), and roughest surface (group Ra 3.0).

SEE PDF Full Length Article

Writers: Camila C. de Foggi; Ana L. Machado; Camila A. Zamperini; Darcy Fernandes; Amanda F. Wady; Carlos E. Vergani

Keywords: acrylic resin; biofilm; Candida albicans; hydrophobicity; surface roughness

Abstract

Aim

The aim of the present study was to evaluate the effect of surface roughness (roughness average [Ra] μm) on the hydrophobicity of a denture-base acrylic resin and the initial adherence and biofilm formation of Candida albicans (C. albicans).

Methods

Disk-shaped specimens were divided into six groups: Ra 0.05, Ra 0.2, Ra 0.4, Ra 0.8, Ra 1.5, and Ra 3.0. Water contact angles (WCA) were measured, and the specimens incubated with C. albicans for 90 min (initial adherence, = 108) or 48 h (biofilm formation, = 108). Adhered and biofilm cells were evaluated by c.f.u./mL and 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT), and the correlation between the two methods was evaluated. The surface of the specimens and cells (adhered and biofilm) were also analyzed by scanning electron microscopy (SEM).

Results

Groups Ra 0.05 and 3.0 exhibited the lowest (~75°) and the highest (~100°) WCA mean values, respectively. For both initial adherence and biofilm formation, no statistically-significant differences were observed among all groups, as determined by c.f.u./mL and XTT. A positive correlation between these two methods was found. SEM analysis showed the presence of scratches and valleys on the acrylic specimens and densely-packed yeast cells covering the entire surface.

Conclusions

Roughness significantly increased hydrophobicity (WCA), but had no effect on the number and metabolic activity of adherent and biofilm cells of C. albicans.

Centro de Desenvolvimento de Materiais Funcionais
Sobre Centro de Desenvolvimento de Materiais Funcionais 140 Artigos
O CDMF é um dos Centros de Pesquisa, Inovação e Difusão (CEPID) apoiados pela FAPESP. O Centro também recebe investimento do CNPq, a partir do Instituto Nacional de Ciência e Tecnologia dos Materiais em Nanotecnologia (INCTMN).