Relative presence of , , and in biofilm of complete dentures.

Aims And Objective: Oral biofilms in denture wearers are populated with a large number of bacteria, a few of which have been associated with medical conditions such as sepsis and infective endocarditis (IE). The present study was designed to investigate the relative presence of pathogenic bacteria in biofilms of denture wearers specifically those that are associated with IE.

Methods: Biofilm samples from 88 denture wearers were collected and processed to extract total genomic DNA. Eight of these samples were subjected to 16S rRNA gene sequencing analysis to first identify the general bacterial occurrence pattern. This was followed by species-specific quantitative polymerase chain reaction (qPCR) on entire batch of 88 samples to quantify the relative copy numbers of IE-associated pathogens.

Results: 16S rRNA gene analysis of eight biofilm samples identified bacteria from , , , and species. Interestingly, , , and from , all known to be associated with early-onset sepsis and IE was present in five of eight biofilm samples. The other three samples carried bacteria from genus with and , which are known to be commensals, as dominant species. Species-specific qPCR of , and on 88 biofilm DNA samples identified the presence of in 83%, in 79%, and in 76% of samples.

Conclusion: The findings from the present study demonstrate co-occurrence of , , and in a majority of denture wearers, which is clinically significant as elderly patients with compromised immune system are more prone to develop IE. To the best of our knowledge, the co-occurrence of , , and is being reported for the first time in biofilms of denture wearers.