Effects of Non-Surgical Periodontal Therapy on Gingival Crevicular Fluid Levels of Interleukin-17 and Interleukin-23 in Patients with Periodontitis: A Clinical Trial

Background and Aim: Considering the critical role of inflammatory responses in periodontal disease, knowledge about the immune system and cytokines seems nec-essary. The aim of this study was to evaluate the level of IL-23 and IL-17 in gingival crevicular fluid (GCF) of patients with chronic and aggressive periodontitis, before and after non-surgical periodontal therapy. Materials and Methods: In the present clinical trial, GCF samples were collected from 54 patients (with aggressive and chronic periodontitis) before and after the ini-tial phase of periodontal therapy. The cytokine concentration was measured using ELISA. The Wilcoxon signed-rank test was performed to analyze the effect of non-surgical periodontal therapy on each group. The correlation between variables was investigated by the Spearman’s correlation coefficient. Results: Non-surgical periodontal therapy in both groups significantly decreased the IL-17 and IL-23 levels (P<0.05). A significant correlation was noted between the con-centration of IL-23 and IL-17 before the treatment in the chronic periodontal group (P<0.05), while such a correlation was not seen in the aggressive periodontitis group (P>0.05). Conclusion: Due to the reduction of IL-17 and IL-23 after nonsurgical periodontal therapy, these factors may play a role as mediators of periodontitis pathogenesis. Di-rect statistical correlation between the concentration of IL-17 and IL-23 before treat-ment in the chronic group shows the possible role of IL-23 in inducing Th-17 cells and production of IL-17.