Adipose tissue produces and releases a variety of inflammatory factors, including adipocytokines , such as adiponectin, leptin, tumor-necrosis factor alpha (TNF-α), interleukin-6 (IL-6), visfatin, vaspin and omentin.These adipokines have widespread effects on carbohydrate and lipid metabolism and appear to play an important role in the pathogenesis of insulin resistance, diabetes, inflammation, wound healing, and immune responses.Recently, studies evaluated the serum vaspin and omentin levels as inflammatory markers in T2DM patients. Based on the above mentioned studies, the present investigation has been devoted to elucidate the role of adipokines in the pathogenesis that might link DM and periodontal disease. We hypothesize that vaspin and omentin are inflammatory adipokines involved in chronic inflammation and are associated with T2DM and CP. Additionally, the evaluation of GCF vaspin and omentin levels can provide advance the biologic link between DM and periodontitis. Until now, levels of GCF vaspin and omentin in CP patients with T2DM before and after non-surgical periodontal treatment has not been explored. Hence, the aim of the present study were 1) to determine the role of these adipokines in the pathogenesis of periodontal disease, inflammation and tissue destruction comparing with GCF levels of TNF-α, which has a known pro-inflammatory effect in periodontal disease 2) to investigate the effect of non-surgical periodontal treatment on GCF vaspin and omentin levels in T2DM patients with CP.

A total of 15 T2DM patients with CP ( DM-CP group), 15 CP patients (CP group), 15 T2DM patients (DM-CTRL group) and 15 subjects with systemically and periodontally healthy control subjects (CTRL group) were included in the study. Diabetic subjects should have T2DM and had no any known systemic diseases other than T2DM. The glycemic status of patients previously diagnosed with T2DM was confirmed by their glycated haemoglobin (HbA1c) levels. Periodontal disease status was determined according to clinical and radiographic criteria by the 1999 classification of periodontal disease.

Subjects were clinically evaluated using the following parameters; plaque index (PI), gingival index (GI) , PD, clinical attachment level (CAL) and BOP (deemed positive if it occurred within 15 seconds after probing). Clinical measurements were recorded by one calibrated examiner at six sites per tooth from the full-mouth teeth excluding third molars using with a Williams periodontal probe (Nordent Manufacturing Inc., ElkGrove Village, IL, USA) calibrated in millimeters. Anthropometric measurements included weight (kg) and height (m) of the subjects to calculate the BMI ( weight divided by the square of height, kg/m2 ).

All clinical and radiological examinations, sampling site selections were performed by one examiner and the samples were collected on the day after clinical examination of patients. This was to prevent contamination of GCF with blood associated with the probing of inflamed sites. The deepest two pocket sites of single-rooted teeth were selected for the collection of GCF in both periodontitis groups, and also two pocket sites with an absence of inflammation were sampled to ensure the collection of an adequate amount of GCF in control groups. In patients from CP and DM-CP groups, sites showing greatest PD when measured with a periodontal probes and signs of inflammation, along with radiographic conformation of bone loss were sampled. GCF samples were collected at baseline and after 8 weeks from baseline sampling in both periodontitis groups, and only at baseline in control groups. To avoid salivary contamination, the sites to be sampled were rinsed with water, isolated by cotton rolls and gently air dried. Paper strips (Periopaper; Oraflow Inc.,Smithtown, NY, USA) were gently inserted 1-2 mm into the sulcus/pocket for 30 seconds. Care was taken to avoid mechanical injury of the gingival tissues. All samples containing blood and saliva were discarded. The two strips from two sites of each individual were placed into coded sealed plastic eppendorf tubes and pooled before freezing at -80 degree