Supplementary Material for: The in vivo Inhibition of Oral Biofilm Accumulation and Streptococcus mutans by Ceramic Water

Combustion-synthesized titanium carbide ceramics uniformly disperse
silver, producing silver ions and hydroxyl radicals in water. This
generates antimicrobial activity against various bacteria. One such
bacterium is Streptococcus mutans, a gram-positive anaerobic
bacterium known as a major pathogen of dental caries. In this study, we
analyzed the inhibition of oral biofilms and S. mutans by ceramic water in in vitro and human studies. S. mutans
strains showed significantly lower antimicrobial and sucrose-dependent
adhesion activity in the presence of ceramic powder compared with
untreated culture medium. Confocal microscopy revealed that S. mutans
biofilm structures with ceramic powder were thin and coarse.
Twenty-seven volunteers (13 males, 14 females; 18-37 years old, mean
25.2 years) were enrolled for subsequent studies. After each meal, one
group was asked to rinse with ceramic water while the other rinsed with
untreated water for 1 week. After 1 week, the rinsing contents were
switched between the groups and the same protocol was followed for an
additional week. After rinsing with ceramic water, the average plaque
score was 43.0 ± 3.7, which was significantly lower than the baseline
value (74.1 ± 5.7, p < 0.001). However, no significant
difference was observed when rinsing with untreated water. In addition,
the total number of S. mutans in saliva was significantly reduced after rinsing with ceramic water compared with untreated water (p < 0.05). These results suggest that ceramic water possesses antimicrobial activity against S. mutans and inhibits biofilm formation. Rinsing with ceramic water can also inhibit dental plaque formation and S. mutans colonization in humans.