The results show that when comparing the salivary s-IgA levels of patients with high dental caries and patients with low dental caries (Figure 5A), we found that the salivary s-IgA levels of patients with high dental caries were significantly lower than those of patients with low dental caries (SMD = −0.89, 95%CI: [−1.46; −0.31], P=0.003). This evidence concerns the gene CD79A and dental caries.