In vitro and in vivo removal of oral Candida from the denture base.

OBJECTIVES: To clarify the effectiveness of ultrasonic cleaning for removing Candida lodged in the denture base. MATERIALS AND METHODS: In vitro - Specimens of acrylic resin for denture plates contaminated with Candida cells were ultrasonically cleaned for 30 min. Washings were sampled every 5 min and cultured to investigate residual contamination, measured as colony forming units/ml, and the surfaces of the specimens were subjected to low-vacuum scanning electron microscopy (LV-SEM). In vivo - A total of 24 maxillary denture bases were brushed for 2 min under running tap water, then ultrasonically cleaned for 30 min. The washings were sampled every 5 min and cultured to investigate residual contamination. RESULTS: In vitro - Maximum removal was achieved during the first 5 min of cleaning, with the mean CFU/ml counts significantly declining over time. More than 85% of all Candida was removed within the first 15 min in specimens inoculated with phosphate-buffered saline suspensions of Candida albicans and Candida glabrata. LV-SEM revealed a decreased number of Candida on the surface of the specimens after 30 min of ultrasonic cleaning. In vivo - Maximum removal was achieved during the first 5 min of cleaning, then the mean CFU/ml count significantly declined during the first 10 min. Ultrasonic cleaning for 15 min removed 88.4% of Candida species from the denture base. CONCLUSIONS: Ultrasonic cleaning is a reliable and simple method for removing Candida lodged in the denture base.

Use of Candida-specific chicken egg yolk antibodies to inhibit the adhering of Candida to denture base materials: prevention of denture stomatitis.

OBJECTIVES: Polyclonal anti-Candida chicken egg yolk antibodies (anti-IgY) were used to investigate the prevention of adherence of Candida species to denture base material in vitro. BACKGROUND: Candida is a potential virulence factor that can cause systemic infection and even death in immunocompromised individuals. Because long-term antifungal treatment may lead to the emergence of drug-resistant strains, it is necessary to develop novel preventive measures and treatments for candidiasis. MATERIALS AND METHODS: Three types of chicken egg yolk antibodies were used in this study: non-specific antibody (control IgY), Candida albicans-specific antibody (anti-C.a.IgY) and Candida glabrata-specific antibody (anti-C.g.IgY). A mixture of different dilutions of each antibody with a suspension of Candida species and denture base material was incubated for 3 h, and then the colony-forming units of Candida on the denture base material were counted. RESULTS: Compared with control IgY, anti-C.a.IgY and anti-C.g.IgY significantly inhibited the adherence of C. albicans, but anti-C.a.IgY tended to be more potent than anti-C.g.IgY. The adherence of C. glabrata was also inhibited significantly by anti-C.a.IgY and anti-C.g.IgY with almost equivalent potency, indicating that their actions against C. glabrata were comparable. CONCLUSIONS: This study revealed the inhibitory effects of anti-C.a.IgY and anti-C.g.IgY against the adherence of C. albicans and C. glabrata to denture base material. This finding indicates the possibility of a beneficial effect of IgYs for the prevention of denture stomatitis and candidiasis in clinical settings.