Several studies have analyzed the levels of IL‐23 and IL‐17, as well as their receptors (IL‐23R and IL‐17R), during different stages of periodontal disease and in various types of biological samples, including saliva [8], serum [9], plasma [10, 11], gingival crevicular fluid (GCF) [12], and GT [11, 13–18]. This evidence concerns the gene IL17A and periodontal disorder.