In vitro Comparison of Three Different Methods of Denture Base Acrylic Resin Process in Attachment and Colonization of Candida Albicans

Candidiasis is the most common fungal infection in oral cavity, usually caused by Candida albicans. Since one of the most common complications of denture wearing is denture stomatitis, presence of opportunistic microorganisms such as C. albicans and colonization of denture base by these microorganisms, the aim of this study was to compare the effects of three different methods of acrylic resin processing on adherence and colonization of C. albicans. In this experimental study, 60 square acrylic resin samples, measuring 10×10×10 mm3 (Ivoclar Vivadent, Liechtenstein) were processed with three methods of preparation: cold-cured [CC], heat-cured [HC] and injection-molded [IM]. Yeast suspensions were incubated on the surface of resin blocks for 40 minutes and then washed with 1 mL of sterile saline solution; 20 µL of this solution were inoculated on Sabouraud dextrose agar and incubated at 37 C. The colony counts were determined after 24 and 48 hours. At 60- and 120-minute intervals the colony counts were determined again. Data were analyzed with SPSS 20, using two-way ANOVA and paired t-test (α = 0.05). The method of preparation of acrylic resin (p value = 0.001) and duration of proximity of acrylic resin with the yeasts (p value < 0.001) were significant. The lowest colony counts were observed in the cold-cured method. In all these three methods and durations of proximity of acrylic resin and C. albicans, the colony counts at 48 hours were significantly higher than those at 24 hours (p value < 0.001). The acrylic resin preparation method affected the adhesion and colonization of C. albicans. Considering the lower colonization in cold-cured acrylic resin, it is the most appropriate acrylic resin, especially for those with poor oral hygiene or those susceptible to fungal infections.