Analysis of the oral microbiome on the surface of modified dental polymers.

Objectives: This study characterized the microbial diversity of formed biofilm on the surface of acrylic resins modified with nanostructured silver vanadate decorated with silver nanoparticles (AgVO) after incubation in human saliva.

Design: Resin specimens prepared with AgVO at concentrations 0%, 1%, 2.5%, and 5% by either vacuum mixing or polymer solubilization were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). After 24 h and 7 days of saliva incubation, biofilm samples were collected from the surface of the specimens. The 16S rDNA genes were amplified, sequenced with the 454-Roche next-generation sequencing platform and analyzed to identify the Operational Taxonomic Units at the genus or higher level.

Results: Significant differences in the dispersion pattern of the nanoparticles were observed among the two different methods of AgVO incorporation. In the microbiological analysis, a total of 103 genera and 7 more inclusive taxa, representing the phyla Bacteroidetes, Firmicutes and Proteobacteria were identified colonizing resin surfaces. The incorporation method of the AgVO had little to no significant effect on the microbiota of samples. Significant time and concentration-dependent responses to AgVO caused changes in the taxonomic profile at the phylum and genus level.

Conclusions: The results show differences in relation to the microbial diversity of modified resins during the initial phase of biofilm maturation. The incorporation of AgVO seems to significantly affect the colonizing microbiota.