The presence of YKL- 40 an acute phase protein in both chronic periodontitis and rheumatoid arthritis. However, till date no studies has been done on the levels of gingival crevicular fluid YKL-40 following scaling and root planing, the present study which is first of its kind is designed to detect and estimate the gingival crevicular fluid YKL-40 levels in healthy patients, chronic periodontitis and patient with chronic periodontitis having rheumatoid arthritis at baseline and chronic periodontitis having rheumatoid arthritis 6 weeks post periodontal therapy (scaling and root planning [SRP]). This could throw more light on it and extend our knowledge on its role in both the conditions.

Periodontal diseases is a chronic inflammatory diseases initiated by microbial infection that leads to a host response resulting in inflammatory breakdown of tooth supporting, osseous and soft tissue structures YKL-40 also called as human cartilage glycoprotein-39(HC-gp39), an acute phase protein is a novel potential bio marker in relation to both acute and chronic inflammations. YKL-40 is a member of "mammalian chitinase- like protein" but has no chitinase/ enzymatic activity, with molecular weight of approximately 40KDa. It is named from three amino acids of Tyrosine (Y), Lysine (K) and leucin (L) at the N-terminal YKL-40 was identified in gingival crevicular fluid (GCF) and serum among gingivitis and periodontitis individual with or without diabetic mellitus. Investigation was done in association between chronic periodontitis and diabetic mellitus in gingival crevicular fluid sample. However, the past studies have reported an increased prevalence of rheumatoid arthritis in patient with periodontal diseases. They have reported the presence of rheumatoid factor in gingiva, sub gingival plaque, saliva and serum of periodontally diseased patient. Treatment of periodontal disease has demonstrated significant reduction in erythrocyte sedimentation rate (ESR) which in turn have showed improvement of clinical indices on rheumatoid arthritis activity.we speculate that presence of YKL 40 an acute phase protein in both chronic periodontitis and rheumatoid arthritis. However, till date no studies has been done on the levels of gingival crevicular fluid YKL-40 following scaling and root planing, the present study which is first of its kind is designed to detect and estimate the gingival crevicular fluid YKL-40 levels in healthy patients, chronic periodontitis and patient with chronic periodontitis having rheumatoid arthritis at baseline and chronic periodontitis having rheumatoid arthritis 6 weeks post periodontal therapy (scaling and root planning [SRP]). This could throw more light on it and extend our knowledge on its role in both the condition

Inclusion Criteria:

• 1. Age group of 25 to 55 years. 2. Patient diagnosed with active rheumatoid arthritis with DAS scoring between ≥3.2 to ≤5.1 3. Patient with generalized mild to moderate chronic periodontitis. 4. Patient who had not received any periodontal treatment in last six months. 5. Dentition with at least twenty functioning teeth. 6. Patient who are co-operative and able to attend follow-up.

Exclusion Criteria:

• 1. Any systemic diseased such as diabetic mellitus and thyroid diseases. 2. Former and current smokers. 3. Pregnant and lactating females. 4. Usage of antibiotics or patients on Diseases Modifying Anti-Rheumatic Drugs (DMARD) that affects the periodontal status in the last six months.

IPD are personal informations of patients and its confidential .