To estimate the levels of gingival crevicular fluid YKL-40 in patients with chronic periodontitis and rheumatoid arthritis with chronic periodontitis - a clinico-biochemical study

Background and objectives: YKL-40, a C-reactive protein belongs to the positive acute-phase protein. It is also known as Human chitinase-3-like protein 1(HCI3L1) and is closely related to both acute and chronic inflammation. The present study aimed to detect and estimate the levels of YKL-40 in gingival crevicular fluid (GCF) in patients with healthy periodontium, chronic periodontitis, and rheumatoid arthritis with chronic periodontitis. Materials and methods: Forty-five patients in the age range of 25-55years were included in the study. Patients were divided into three groups: Group I-15 Periodontal healthy patients, Group II-15 Chronic Periodontitis patients, and Group III-15 Rheumatoid arthritis with chronic periodontitis patients. Clinical parameters recorded were Plaque index, Gingival index, Gingival bleeding index, probing depth, and Relative attachment level. GCF samples were analyzed using ELISA. p - value < 0.05 was considered statistically significant. Results: The highest mean YKL-40 concentration in GCF was observed in rheumatoid arthritis with Chronic periodontitis. The mean concentration of YKL-40 in GCF showed a three to four folds increase in its levels when compared to healthy controls (p < 0.001). Contrary, GCF YKL-40 levels between Group II and Group III were not significant. Conclusion: With the increase in severity of periodontal destruction from healthy periodontium to chronic periodontitis, there was a substantial increase in the concentration of YKL-40 in GCF. Correlation of GCF YKL-40 with clinical parameters demonstrated increased severity of the diseases increased its levels