Fig 1.
S. mutans biofilms formation and experimental scheme.
Fig 2.
The smoking device.
Fig 3.
Change in the microbiological and biochemical composition of the 74-h-old S. mutans UA159 biofilms exposure with CS.
(A) Dry weight. (B) CFUs. (C) Water-insoluble EPSs. (D) Water-soluble EPSs. (E) IPSs. Data represent mean ± standard deviation. Fig 3A and 3C and 3D and 3E, p < 0.05. Fig 3B, p > 0.05 *p < 0.05: significantly different from each other. p > 0.05: values followed by the same superscript are not significantly different from each other.
Fig 4.
Change in the pH values of old culture medium exposure with CS during 74-h-old S. mutans UA159 biofilms formation.
Data represent mean ± standard deviation. Values followed by the same superscript are not significantly different from each other (p > 0.05).
Fig 5.
Change in CLSM of bacterial cells in the 74-h-old S. mutans UA159 biofilms exposure with CS.
(A) Bacterial biovolume. (B) Bacterial thickness. (C) Representative confocal images. (D) Total biovolume (live + dead cells). (E) Percent of the total biovolume. Significantly different from each other (p < 0.05).
Fig 6.
Change in CLSM of EPSs in the 74-h-old S. mutans UA159 biofilms exposure with CS.
(A) EPSs biovolume. (B) EPSs thickness. (C) Representative confocal images. Significantly different from each other (p < 0.05).
Fig 7.
Change in the biofilm density of 74-h-old S. mutans UA159 biofilms exposure with CS.
Values followed by the same superscripts are not significantly different from each other (p > 0.05).
Fig 8.
Surface morphology of hydroxyapatite disks before the experiment and each group after 74-h-old incubation.
(A) Before the experiment. (B) Control group. (C) 1 time/day CS exposure group. (D) 3 times/day CS exposure group. (E) 6 times/day CS exposure group.