RESUMO
BACKGROUND: In the last few years unusual microorganisms have been isolated from subgingival biofilm, as possible initiators or contributors to periodontal disease, especially in patients who show no improvement during treatment. AIMS: To study the Candida invasion of the connective tissue in relation to subgingival biofilm presence. METHODS: A total of 55 immunocompetent patients of both sexes, between 21 and 55 years of age, non-smokers, without previous antimicrobial treatment, suffering periodontal diseases, were studied. Soft tissues, supragingival and subgingival plaque samples, and periodontal pocket biopsies were taken. Microscopic studies, cultures, assimilation profiles, and DNA amplifications were performed. RESULTS: In 35% of the samples, different species of Candida were isolated in cultures, especially Candida albicans. Hyphae invasions in the connective tissue were observed, in association with anaerobic microorganisms (Porphyromonas gingivalis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans) in patients with periodontitis. CONCLUSIONS: Different species of Candida could be part of the periodontal plaque and could play an important role in the adherence to soft tissues, allowing deep invasion. They also could infect gingival pockets in patients with gingivitis, even in healthy locations, playing a commensal or opportunist role.