Impact of frequency of denture cleaning on microbial and clinical parameters – a bench to chairside approach

Abstract

Objective: Robust scientific and clinical evidence of how to appropriately manage denture plaque is lacking. This two-part study (i) developed an in vitro model of denture plaque removal, and (ii) assessed effectiveness of these approaches in a randomised clinical trial.Method: (i) a complex denture plaque model was developed using the dominant microbial genera from a recent microbiome analyses. Biofilms formed on polymethylmethacrylate were brushed daily with a wet toothbrush, then either treated daily for 5 days or only on Days 1 and 5 with Polident® denture cleanser tablets (3 min soaking). Quantitative and qualitative microbiological assessments were performed. (ii), an examiner-blind, randomised, crossover study of complete maxillary denture wearers was performed (n = 19). Either once-daily for 7 days or on Day 7 only, participants soaked dentures for 15 min using Corega® denture cleansing tables, then brushed. Denture plaque microbiological assessment used sterilized filter paper discs.Results: The in vitro model showed daily cleaning with denture cleanser plus brushing significantly reduced microbial numbers compared to intermittent denture cleaning with daily brushing (p < 0.001). The clinical component of the study showed a statistically significant reduction in denture plaque microbial numbers in favour of daily versus weekly treatment (aerobic bacteria p = 0.0144). Both in vitro and in vivo studies showed that denture plaque biofilm composition were affected by different treatment arms.Conclusions: This study demonstrated that daily denture cleansing regimens are superior to intermittent denture cleansing, and that cleansing regimens can induce denture plaque compositional changes. Clinicaltrials.gov registration: NCT02780661.

A nanocarrier system that potentiates the effect of miconazole within different interkingdom biofilms

“…To assess the effect of IONPs-CS-MCZ on pathogenic biofilms, three different in vitro multi-species biofilm models were tested, representative of caries, denture and gingivitis developed as previously described [4,27,28]. For all biofilm models, the bacterial and fungal cells were adjusted to 1 × 10 7 cells/mL in Todd Hewitt Broth (THB) medium supplemented with 0.01 mg/mL hemin and 2 µg/mL menadione [29].…”

“…Biofilm development for all models used followed similar protocols as described previously [4,27,28,30]. Briefly, biofilm formation consisted of inoculating Streptococcus species and C. albicans(500 µL) on the first day to promote primary colonization, followed by the addition of the remaining species on the second day.…”

“…A qPCR viability method was used to count the microbial cells and determine the composition of the biofilm models, as previously described [4,30]. In short, the sonicated samples from above were split into 2 Eppendorf tubes.…”

“…For qPCR,1 µL of sample DNA was added to a mastermix solution containing 10 µL of SYBR GreenER TM (Thermo-Fisher, UK), 7 µL of UV-treated RNase-free water and 1 µL of 10 µM forward/reverse primers for each microbial genus or species. Table 1 displays the primers used in the study [4,27,28]. A total volume of 20 μl was added to MicroAmp fast-optical 96-well 0.1 ml reaction plates (Applied Biosystems, USA) and loaded into the StepOnePlus™ real time system (Applied Biosystems, USA).…”

Polymicrobial oral biofilm models: simplifying the complex

“…The ensuing studies from the group have enhanced our understanding of the host response to commensal and pathogenic biofilms. A recent publication by Ramage et al (126) developed a complex denture plaque model using the dominant microbial genera from a microbiome study (104). Future models may serve to utilise OMICs approaches such as microbiome analyses to develop new biofilm models incorporating microorganisms newly associated with oral diseases such as denture stomatitis, periodontitis or endodontic infections.…”