Comparison between static and semi-dynamic models for microcosm biofilm formation on dentin

Abstract

Microcosm biofilm has been applied to induce carious lesions in dentin. However, no study has been done to compare the impact of the type of model for providing nutrients to microcosm biofilm formation on dentin.ObjectiveThis study compared the performance of two kinds of models (static and semi-dynamic) on the biofilm formation and the development of dentin carious lesions.Material and MethodsIn both models, biofilm was produced using inoculum from pooled human saliva mixed with McBain saliva for the first 8 h (5% CO2 and 37°C). Afterwards, for the static model, the samples were placed in 24-wells microplate containing McBain saliva with 0.2% sucrose, which was replaced at 24 h. In the semi-dynamic model, the samples were submitted to artificial mouth system with continuous flow of McBain saliva with 0.2% sucrose (0.15 ml/min, 37°C) for 10 h a day (for the other 14 h, no flow was applied, similarly to the static model). After 5 days, biofilm viability was measured by fluorescence and dentin demineralization by transverse microradiography.ResultsBiofilm viability was significantly lower for the static compared with semi-dynamic model, while dentin demineralization was significantly higher for the first one (p<0.05). The static model was able to produce a higher number of typical subsurface lesions compared with the semi-dynamic model (p<0.05).ConclusionsThe type of model (static and semi-dynamic) applied in the microcosm biofilm may have influence on it's viability and the severity/profile of dentin carious lesions.

Implication of Surface Properties, Bacterial Motility, and Hydrodynamic Conditions on Bacterial Surface Sensing and Their Initial Adhesion

“…Various artificial mouth models containing a continuous flow of saliva have been applied while mimicking the temperature, pH, and sucrose supply in the oral cavity. In a recent study done by Santos et al (2019), they compared biofilm formation in static and semi-dynamic conditions by utilizing McBain saliva. They found that the biofilm viability was significantly lower for the static model than the semi-dynamic counterpart (Santos et al, 2019).…”

“…In a recent study done by Santos et al (2019), they compared biofilm formation in static and semi-dynamic conditions by utilizing McBain saliva. They found that the biofilm viability was significantly lower for the static model than the semi-dynamic counterpart (Santos et al, 2019).…”

Novel Nanocomposite Inhibiting Caries at the Enamel Restoration Margins in an In Vitro Saliva-Derived Biofilm Secondary Caries Model

“…The following three aspects should be noted. First, human saliva and sucrose were commonly used to establish in vitro dental plaque biofilm secondary caries models [ 23 , 57 , 58 ]. Microcosm biofilms from human saliva are similar to natural plaque and overcome many difficulties encountered in studying in vivo biofilms, such as lack of standardization among subject characteristics [ 59 ].…”

Antimicrobial and cytotoxic capacity of pyroligneous extracts films of Eucalyptus grandis and chitosan for oral applications

“…In fact, the biofilm model is one of the closest simulations to in vivo models, making it possible to more accurately reproduce the complexity of a real dental biofilm in vitro 32 – 34 . The use of saliva or dental plaque as an inoculum for biofilm formation in microtiter plates is certainly the most commonly used method 35 . Human saliva was used as the inoculum with bovine enamel as substratum.…”