Influence of Surface Properties on Candida albicans Adhesion to Denture Base Materials Fabricated by Different Techniques

Abstract

Objectives: This in vitro study evaluated and compared the surface roughness, wettability (contact angle), and Candida albicans (C.albicans) adhesion of denture base materials fabricated by different methods. Materials and Methods: Six materials were tested: conventional heat-polymerized polymethyl methacrylate (PMMA) resin (Meliodent; Kulzer GmbH, Germany), CAD/CAM PMMA-based polymer (KeyMill; Keystone Industries, USA), CAD/CAM polyetheretherketone (PEEK) block (Audental; Shenzhen, China), thermoplastic polyamide-based resin (Nuxen; SRL, Argentina), titanium alloy block (Grade V, Ti-6Al-4V) (Audental; Shenzhen, China), and cobalt-chromium (Co-Cr) alloy (Wironit; BEGO GmbH, Germany). Surface roughness (Ra) and contact angle (°) were measured, and C. albicans adhesion was quantified as colony-forming units per milliliter (CFU/mL). Data were analyzed using Kruskal-Wallis and Mann-Whitney U tests with Bonferroni correction; correlations were examined with Spearman's coefficient. Results: Significant differences were found among materials for surface roughness, contact angle, and C. albicans adhesion (p < 0.05). Conventional PMMA, polyamide, and PEEK showed the highest roughness; Co-Cr and titanium had the lowest. Co-Cr displayed the highest contact angle, titanium the lowest. C. albicans adhesion was greatest on polyamide and PEEK, and lowest on Co-Cr. Surface roughness correlated positively with fungal adhesion (ρ=0.676, p < 0.001), while contact angle showed no significant correlation (ρ = 0.006, p = 0.964). Conclusions: Surface roughness was the main factor influencing C. albicans adhesion; smoother surfaces reduced fungal colonization. Choosing denture base materials with low roughness may help limit biofilm formation and prosthesis-related infections.