Figure 1. Dental plaque architecture: the EPS matrix, spatial organization and polymicrobial composition.

Plaque biofilm from caries-active subject (photo courtesy of Dr. Jaime A. Cury): microscopic image (inset) of plaque-biofilm showing a selected area containing bacterial cells (highlighted in orange) enmeshed in EPS (in dark blue); the image was pseudo-colored using ADOBE Photoshop software for visualization purposes (adapted from Hajishengallis et al., 2016 [19]). The middle panel shows bacterial clusters (green) surrounded by EPS matrix (red) detected in mature mixed-species oral biofilms formed in sucrose (adapted from Koo & Yamada, 2016 [5]). The right panel displays the spatial organization of human dental plaque showing multiple clusters of varying sizes containing different microbial species (adapted from Mark Welch et al., 2016 [31]).