RESUMO
AIM: This study evaluated the antibiofilm effect of an experimental solution of 2% Ricinus communis (R. communis) on a silicone-based denture liner by means of a randomized clinical trial, as well as the integrity of such liner following a cleansing regimen with such solution. MATERIALS AND METHODS: About 30 complete denture wearers had their lower dentures relined with a silicone-based denture liner and randomly allocated to cleanse their dentures by means of: (A) a specific toothbrush for complete dentures and dentifrice; (B) soaking in an experimental 2% R. communis solution; and (C) association of A and B. Considered outcomes were biofilm coverage area (%), microbial counts by means of the deoxy-ribonucleic acid (DNA) checkerboard hybridization technique and physical integrity of the soft liner, assessed during a time interval of 60 days. Mean group values were compared by analysis of variance (ANOVA) and Tukey tests or generalized linear method (α = 0.05). RESULTS: The mechanical method presented the lowest biofilm percentage (1.45 ± 1.03) if compared to the chemical method (2.96 ± 1.98) and the associated one (2.71 ± 1.76). After 60 days (3.37 ± 2.04), biofilm accumulation was higher than at 15 days (1.28 ± 0.77) and 30 days (2.46 ± 1.54). The denture liner was less deteriorated and kept its physical integrity when the mechanical method was applied. The chemical method presented higher effectiveness against microorganisms, including some Candida species. CONCLUSION: The 2% R. communis solution presented stronger antimicrobial capacity than brushing on a silicone-based denture liner after immersion. However, it was not superior to the mechanical method in preserving the physical integrity of the material and in biofilm removal. CLINICAL SIGNIFICANCE: Soft denture liners hygiene is a very important issue and not conclusive in the literature. The experimental solution of 2% R. communis evaluated presented promising antimicrobial potential and should be more explored to be recommended as cleanser.