Brushing associated with oral irrigation in maintaining implants and overdentures hygiene - a randomized clinical trial.

Evaluate, through a randomized clinical trial, the efficacy of brushing associated with oral irrigation in maintaining implant and overdenture hygiene. Thirty-eight participants, who had a clinically acceptable conventional maxillary complete denture and mandibular overdenture retained by either implants or mini-implants using an O-ring-retained system, were enrolled to participate in the study. They were instructed to use two different hygiene methods, in a random sequence for a period of 14 days, with a 7-day wash-out interposed period: (I) mechanical brushing (MB); (II) association of mechanical brushing with oral irrigation (WP). Biofilms from both subgingival sulci and overdentures were collected and processed by Checkerboard DNA-DNA hybridization method at baseline and after using the proposed hygiene protocols. Comparisons were performed using Wilcoxon test and Friedman test with Benjamini-Hochberg false discovery rate, followed by Conover post-hoc test (α = 0.05). In the subgingival sulci-related biofilm, a lower number of microbial cells were detected, after WP compared to the MB method (P < 0.001). The findings of overdenture-related biofilm suggest that both methods were similar (P = 0.607) being the identified microbiota qualitatively coincident after each method. Despite the number of microbial counts, it was concluded that the association of mechanical brushing with oral irrigation was more effective in reducing microorganisms in the subgingival sulci biofilm; however, the same outcome was not observed in the overdentures.