Efeito de um colutório experimental em biofilme polimicrobiano formado sobre superfícies abióticas

Abstract

Dental implants are widely used for oral rehabilitation; however, they are also substrates where microbial adhesion and biofilm accumulation can occur, which can lead to inflammation, loss of osseointegration, and even loss of the dental implant. Several therapeutic possibilities are studied to try to minimize this damage, since the prevalence of peri-implant complications, although variable, has been shown to be increasing. In this study, the antimicrobial activity of an experimental mouthwash with 1% cinnamaldehyde was evaluated in vitro in a polymicrobial biofilm model, from the saliva of donors with periodontal health (SS) and donors with gingivitis (SG), on titanium and zirconia surfaces that simulated rehabilitation, with an implant and its prosthetic crown. Polymicrobial biofilms were seeded (1x108 CFU/mL) on zirconia (n=6/group) and titanium(n=6/group) surfaces from stimulated saliva collection from 2 donors with periodontal health (SS) and donors with gingivitis (SG). Salivary pools were performed by condition type (healthy and gingivitis). Specimens were subjected to salivary pellicle formation for 60 minutes. Inoculum was seeded (1x108 CFU/mL) in McBain medium supplemented with 10% filtered saliva, and the biofilms were cultured in microaerophilic conditions for 24 hours. Daily challenges with 10% sucrose were performed three times a day, followed by medium change. After the initial 72 hours, the medium was aspirated from all wells, and the samples were exposed to the experimental mouthwash for 1 minute, twice a day, for 72 consecutive hours. Chlorhexidine digluconate 0.12% and saline solution (0.9% NaCl) were used as controls. Biofilms were kept in culture for an additional 24 hours, completing a total culture time of 168 hours for subsequent counting of the number of viable cells (CFU/mL) in the ASD (Sabouraud Dextrose Agar), BHI (Brain Heart Infusion) and MAS (Mitis Salivarius Agar) media, biomass evaluation using the crystal violet (CV) test and metabolic evaluation of the biofilm using the methyltetrazolium salt test (MTT assay). Data were analyzed by inferential statistics using the Kruskal-Wallis test complemented by Mann-Whitney or DSCF with a significance level of 5%. Regarding the biofilms seeded on zirconia surfaces, it was observed that no statistically significant differences were detected between the biofilm conditions or between the substances (p>0.05), with no differences for the CFU/mL count, nor for the evaluation of the biomass of the microorganisms evaluated. Regarding the evaluation of cellular metabolism, no statistically