Validation of an in situ model for the formation of non-disturbed oral biofilm

Abstract

The aim of this Thesis was to validate the IDODS as an appropiate model for the formation of non-disturbed oral biofilm. Firstly, a systematic review of the literature was conducted to identify all in situ studies using a specific oral device and analysed oral biofilm microbiologically. In the following chapter, volunteers wore the device from 2 to 4 days. The characteristics (thickness, bacterial viability, covering grade and structure) of the biofilm formed on the device (PL-Biofilm) were analysed using the Confocal Laser Scanning Microscope (CLSM) in combination with LIVE/DEAD® BacLight™ staining solution and complemented with the Scanning Electron Microscope. The CLSM methodology was used to compare the PL-Biofilm versus the tooth-formed biofilm, as well as the antimicrobial activity of two oral antiseptic, (0.2 % of Chlorhexidine solution or Essential Oils), applied by two different methodologies. The 2-days PL-Biofilm and tooth-formed biofilm were also analysed by pyrosequencing of the 16S rDNA gene. The influence of the tooth-brushing protocol during the experiment was analysed with both methodologies (CLSM and pyrosequencing).Based on the results from this Thesis, the IDODS seems to be an appropiate oral biofilm model to test intraorally the immediate effect and antiplaque effect of antiseptic solutions.