An Analytical Tooth Model Based on Surface Plasmon Resonance Chips Coated with Hydroxyapatite Used for Investigation of the Acquired Dental Pellicle

Abstract

One of the main targets in modern dentistry is the prevention of caries. Not only daily nutrition plays an important role, but also the so‐called “pellicle” on the outer surface of teeth, which is mainly formed by saliva proteins. Moreover, numerous bacteria are part of this pellicle, which might cause caries by acidic metabolites. In the here‐presented study, a method for electrophoretic deposition (EPD) of hydroxyapatite (HAP) nanoparticles on gold surfaces, suitable for surface plasmon resonance (SPR) measurements, is developed. An “artificial tooth” is created and loaded by natural saliva in different concentrations (to form a natural pellicle), while the influence of an environment with different pH values has been studied. It could be demonstrated that even slight acid solutions damage the pellicle significantly within seconds, exposing the HAP to acidic degradation, which would lead to caries in the human oral cavities. This model allows to study pellicle formation as well as degradation in real time. As a practical example, the influence of beverages on the pellicle could be demonstrated.