Fig. 1.

Simplified model of the bioadhesion and biofouling processes on sensor surfaces. The pellicle impairs larger molecules from binding directly on the sensor surfaces. It serves as a diffusion barrier which limits access of small molecules and ions on the sensor. Pellicle enzymes and metabolites from bacterial biofilms can influence measurements of the sensors, since they might interfere with underlying enzymatic reactions of biochemical sensors by either inhibiting or promoting these reactions. Salivary electrolytes might influence measurements in amperometric or potentiometric measurements due to their influence on conductivity. Biofouling and biodadhesion process can lead to worse performance of the intraoral sensor, which leads to a very low sensitivity of the sensor