Effectiveness of Hygiene Solutions on Denture Biofilm

This clinical trial evaluated Ricinus communis and sodium hypochlorite solutions in different concentrations for denture cleanliness, regarding biofilm removal capacity, remission of atrophic chronic candidiasis, degree of patient satisfaction and antimicrobial action against specific microorganism. Sixty-four denture wearers with absence (n=40) or presence of Candidiasis (n=24) were selected and oriented to brush their dentures with a specific brush and neutral soap for 3 minutes, 3 times a day and immerse them, once a day, in hygiene solutions (0.25% sodium hypochlorite - S1 and 0.5% - S2, 10% R. communis - S3; Saline - S4: control) during 20 minutes, for 7 days. The solutions were used in a randomized, double blind and cross form with washout periods. To quantify biofilm with software ImageTool 3.0, the inner surface was disclosed (1% neutral red) and photographed at the end of each period. The Candidiasis remission was assessed by scores before and after the use of solutions. Patient satisfaction was assessed by questionnaire. Antimicrobial activity was determined by Colony Forming Units (CFU) counts of Streptococcus mutans, Candida spp., and gram-negative microorganisms. For collecting biofilm, internal surface of each maxillary complete denture was brushed with saline solution, and the biofilm suspension obtained. After serial dilutions (100 - 10-3), 50 uL aliquots were seeded in Petri dishes containing Mitis salivarius agar base, CHROMagar Candida® and MacConkey agar for detecting S. mutans, Candida spp., or gram-negative microorganisms, respectively. After incubation, colonies were counted, and values in CFU/mL were calculated. Biofilm removal was analyzed as a split-plot with two variation factors: inflammation and solutions. The candidiasis remission was analyzed after adjustment using multinomial logistic regression. Logistic regression analysis and compound symmetry was adopted for patient satisfaction. The antimicrobial action was analyzed with Friedman´s test. Antimicrobial action data were processed after transformation - log10 (CFU + 1) - and were analyzed by Friedman test (α = 0.05).