FIG 4.

E-cigarette aerosols promote biofilm the formation of S. mutans but not S. sanguinis and S. gordonii. Overnight cultures of S. sanguinis (A), S. gordonii (B), and S. mutans (C) were diluted 1:10 in e-cig-pretreated medium and grown for 24 h. Biofilms were stained with safranin, and OD₄₉₀ was measured. The data are means and SEM (n = 7) for one biological replicate of 3. Groups were compared to the control using one-way ANOVA (Dunnett’s correction). **, P < 0.01; ***, P < 0.001.