Figure 2.

Alpha diversity analysis of caries-active (CA), periodontitis (P), caries-active and periodontitis (CAP) and healthy controls (H). (A) Rarefaction curves of all samples. The rarefaction curves approached asymptotes for each sample when approximately 5000 sequences were extracted and Good's coverage estimator of each group came up to 99.7%, indicating that the sequencing depth was sufficient. (B) Shannon index and (C) Chao 1 index of each group. When 28,320 sequences were randomly subsampled to obtain equal numbers of sequences from each dataset, the diversity of the four communities had no significant differences based on Shannon index. However, significant differences between P and H, CAP and H were observed under Chao1 index (∗: P value < 0.05).