Evaluation of IL-36ɣ, IL-38, IL-17 and MMP-9 levels in serum, saliva and gingival crevicular fluid samples of periodontal healthy and individuals with periodontal disease

Objective: The aim of this study is to determined and compared the levels of matrix metalloproteinase (MMP)-9, interleukin (IL)-17, IL-36-gamma (γ) and IL-38 in the gingival crevicular fluid (GCF), saliva and serum fluids of individuals with periodontally healthy and periodontal disease, and to evaluated their relationship with clinical parameters. Method: GCF, whole saliva and serum samples were collected from systemically healthy and non-smoker; periodontally healthy (S, n=30), gingivitis (G, n=30) and periodontitis (P, n=30) individuals. Clinical periodontal records of the individuals included in the study, including plaque index (PI), gingival index (GI), pocket depth (PD), clinical attachment level (CAL), and percentage of bleeding on probing (BOP), were recorded. Enzyme-linked immune absorbent method (ELISA) was used for the analysis of the collected samples. Kruskal-Wallis test and Bonferroni correction were performed for multiple comparisons and post hoc statistical analyses, respectively. Results: All clinical parameters; PI, GI, SCD, CAL and BOP (%) showed statistically significant positive correlations among themselves (p<0.001). In the comparison between the groups GCF, saliva and serum MMP-9, IL-17, IL-36γ and IL-38 levels were found to be statistically significantly lower in the healthy group compared to the periodontitis group (p<0.001). Biochemical parameters in all samples were measured in lower amounts in the healthy group than in the gingivitis group, and higher in the periodontitis group compared to both groups. Except for serum MMP-9 concentration, there is a significant positive correlation between clinical parameters and MMP-9, IL-17, IL-36γ and IL-38 levels in other biological fluids (p<0.001). Conclusion: Because of the correlations between MMP-9 and IL-17, which are responsible for tissue destruction in periodontitis, and IL-36γ and IL-38; it is suggesting that IL-38 and IL-36γ may be important biological markers for detecting the unexplained aspects of periodontal disease pathophysiology. On the other hand, although this study is a guide for other studies, there is a need for long-term follow-up studies and more research that using different examination methods.