Fig. 3.

Colonization of dentin. Bisected teeth were incubated for 7 days at 37 °C with R. mucosa. Immediately before fluorescence microscopy, teeth were incubated for 15 min with green-fluorescent dye SYTO9. After removal of the fluorescent dye and a washing step with distilled water, bacteria were visualized using a Zeiss AxioCam MRc5 microscope. Bacteria, which appear as light green spots embedded in biofilm matrix mainly in the middle of the image (indicated by an arrow), are predominantly found at the root canal surface, while the dentin shows an even green auto-fluorescence. Scale bar 50 µm