Fig. 2

Differences within the microbiota in oral biofilm samples of 179 study participants in three different groups and three study centres based on metagenomic sequencing. A PCoA depicting the beta-diversity based on Bray–Curtis dissimilarity of the microbial communities in H, C, P (colours) and the three study centres (shapes; R² = 0.155, p = 0.0001); B comparison of the mean relative abundance in H, C, P (≥ 1% in at least one group). The species shown are significantly differentially abundant between at least two groups based on DESeq2 with a log fold change > 2.5; numbers indicate the mean relative abundances. Healthy (n = 63, 60.3% female), Caries (n = 61, 31.1% female), and Periodontitis (n = 55, 41.8% female)