Subgingival distribution of yeast and their antifungal susceptibility in immunocompetent subjects with and without dental devices.

Yeasts colonize the subgingival biofilm, which becomes a reservoir that favors their reproduction. The purpose of the present work was to determine the prevalence of yeasts of the Candida genus in the subgingival biofilm of gingivoperiodontal disease patients, including users and non-users of dental devices, and their susceptibility to fluconazole and voriconazole. Samples of subgingival pockets of immunocompetent nonsmokers showing gingivitis and periodontitis were inoculated in a differential chromogenic medium. Sixty three percent of subjects used dental devices. Yeasts were identified and susceptibility to fluconazole and voriconazole was tested following CLSI M44-A standards. The prevalence of yeasts in the subgingival biofilm was 40% CI 95% (30.5-50.3); 10% were patients who did not use dental appliances. The most frequently observed yeasts were C. albicans, and C. parapsilosis, C. dubliniensis, C. tropicalis and C. guilliermondii. Only C. dubliniensis and C. guilliermondii showed resistance to azoles. The use of dental devices significantly increased the prevalence of yeasts in periodontal pockets inpatients presenting gingivitis. It is noteworthy that non albicans Candida species, such as C. dubliniensis and C. guilliermondii, considered emerging species, which have a diminished susceptibility to antifungal agents were found in the crevicular fluid of immunocompetent patients.