Figure 2
Treatment with arginine-containing dentifrice alters oral microbial composition. Principal Component Analysis (PCA) of saliva microbiome before (a) and after (b) 2-week arginine-containing toothpaste treatment (n = 21 in each group). Abundance of S. mutans (S. m) (c) and S. sanguinis (S. s) (d) in all types of samples before and after the treatment. Bacterial counts were determined by species-specific qPCR, and normalized with the total bacterial load. Data are presented as standard box plot, with the boxes presenting the first and third quartiles and the whiskers representing the 5th and 95th percentiles. (n = 15; Kruskal-Wallis test followed by Dunn’s multiple comparison test; *p < 0.05, **p < 0.01, ***p < 0.001). (e) Representative images of in situ plaques labeled by S. m- and S. s-specific fluorescent in situ hybridization (FISH) probe. (f) Quantitative analysis of S. m/S. s ratio in the in situ plaques, bacterial loads were measured based on integral optical density (IOD). Data are presented as standard box plot. (n = 3; Kruskal-Wallis test followed by Dunn’s multiple comparison test; **p < 0.05, **p < 0.01). Pre-CF and Post-CF = caries-free group before and after arginine-containing toothpaste treatment respectively; Pre-CA and Post-CA = caries-active group before and after arginine-containing toothpaste treatment respectively.
