The expression of IL-17B was statistically significantly lower in patients with periodontitis in comparison with healthy subjects (median: 0.00017, Q1–Q3: 0.000087–0.0021 vs. median: 0.0042, Q1–Q3: 0.00076–0.012, respectively, p = 0.048), (Figure 2). This evidence concerns the gene IL17B and periodontitis.