The Behaviour of Selected Oral Bacteria in Single- and Mixed-Species Biofilms

The objective of this study was to investigate and compare the adhering capacity of early colonizers of oral biofilm in a dynamic environment. The study was carried out by inoculating the early colonisers of oral biofilm (Streptococcus mitis, Streptococcus sanguinis and Actinomyces sp.) singly and in a mixture to the experimental pellicle in an artificial mouth (NAM) model for 24 h. This will form the respective 24 h single- and mixed-species biofilm. The bacterial population adhering to the experimental pellicle was determined and expressed as colony forming unit per ml (cfu mL super(-1)). The adhered bacterial population was further confirmed using the Scanning Electron Microscope. It was found that S. mitis demonstrated maximum adherence (1153.33c132.46x10 super(4) cfu mL super(-1)), followed by S. sanguinis (183.00c10.33x10 super(4) cfu mL super(-1)) and by Actinomyces sp. (42.33c3.20x10 super(4) cfu mL super(-1)). The adhering capacity of bacteria when present in a mixture of two-species was found to be reduced. However in a mixture of three species, it was found that me bacterial adherence was slightly increased. The difference in the adherence capacity of these bacteria to the experimental pellicle was found to be statistically significant (p