< b > < i > Candida albicans < /i > < /b > Increases Dentine Demineralization Provoked by < b > < i > Streptococcus mutans < /i > < /b > Biofilm

Streptococcus mutans are considered the most cariogenic bacteria, but it has been suggested thatCandida albicans could increase their cariogenicity. However, the effect of this dual-species microorganisms ’ combination on dentine caries has not been experimentally evaluated. Biofilms ofC. albicans,S. mutans andC. albicans +S. mutans (n = 12/biofilm) were grown in ultra-filtered tryptone yeast extract broth culture medium for 96 h on root dentine slabs of known surface hardness and exposed 8 times per day for 3 min to 10% sucrose. The medium was changed 2 times per day (after the 8 cariogenic challenges and after the overnight period of famine), and aliquots were analyzed to determinate the pH (indicator of biofilm acidogenicity). After 96 h, the biofilms were collected to determine the wet weight, colony-forming units, and the amounts of extracellular polysaccharides (soluble and insoluble). Dentine demineralization was assessed by surface hardness loss (% SHL). The architecture of the biofilms was analyzed by confocal laser scanning microscopy (CLSM) and transmission electron microscopy (TEM). Data were analyzed by ANOVA followed by Tukey ’s test (α = 0.05). The dual-speciesC. albicans +S. mutans biofilm provoked higher % SHL on dentine (p #x3c; 0.05) than theS. mutans andC. albicans biofilm. This was supported by the results of biofilm acidogenicity and the amounts of soluble (6.4 ± 2.14 vs. 4.0 ± 0.94 and 1.9 ± 0.97, respectively) and insoluble extracellular polysa...

Source: Caries Research - November 16, 2018 Category: Dentistry Source Type: research