Gingival crevicular fluid and interleukin-23 concentration in systemically healthy subjects: their relationship in periodontal health and disease

Background and Objective There is a substantial magnitude of data implicating the role of interleukin-23 (IL-23) in the initiation and progression of periodontal disease. The main aim of this study was to evaluate the levels of IL-23 in the gingival crevicular fluid of systemically healthy subjects in periodontal health and disease. In addition, we explored the effectiveness of periodontal interventional therapy on the levels of IL-23 in subjects with chronic periodontitis to obtain a deeper insight into the possible role of IL-23 in three separate periodontal conditions in three different populations. Material and Methods In this study, 54 individuals, satisfying the study inclusion and exclusion criteria, were recruited. They were categorically divided, on the basis of gingival index, probing pocket depth and relative attachment loss, into three groups: Group 1 (patients with a clinically healthy periodontium, n=18); Group 2 (patients with gingivitis, n=18); and Group 3a (patients with chronic periodontitis, n=18). Samples taken from all 18 subjects of Group 3a, 3mo after the initial therapy, constituted Group 3b. All clinical parameters were recorded at baseline and 3mo after scaling and root planing. Gingival crevicular fluid samples were obtained in which the IL-23 concentration was measured using ELISA. Results The highest mean IL-23 concentration in gingival crevicular fluid was found for Group 3a (16448.69pg/mL) and the lowest for Group 1 (2565.28pg/mL). The mean IL-23 concentrations in Group 2 (5425pg/mL) and Group 3b (6272.22pg/mL) lay between the maximum and minimum values. This implies a positive correlation between the gingival crevicular fluid IL-23 concentration and relative attachment loss (p<0.05). Conclusion A noteworthy increase in the gingival crevicular fluid IL-23 concentration was seen that was proportional to the amount of periodontal tissue damage. As the IL-23 concentration in gingival crevicular fluid is directly proportional to the severity of the periodontal affliction, it can be speculated that IL-23 has a possible role in the pathogenesis of periodontal disease.