Unstimulated salivary samples were collected using standard techniques. About 2 mL whole saliva was collected in disposable tubes and centrifuged immediately to remove cell debris (10,000 g x 10 minutes). The supernatants (50µL each) were stored at -40C until analyzed. GCF samples were collected from a mesio-buccal and disto-palatal site on each tooth (molars, premolars, canines/incisors). In the CP group, the samples were obtained from patients at areas with ≥5 mm CAL, ≥6 mm PD and ≥30% bone loss. In gingivitis group, GCF samples were obtained from teeth with BOP and without CAL. In the healthy group, GCF samples were collected from teeth exhibiting PD<3 mm without CAL and BOP. Six GCF samples were collected from each patient. The area was isolated with cotton rolls, saliva contamination elimination was ensured, and it was slightly air dried. GCF was sampled with paper strips. Paper strips were placed into the crevice until mild resistance was felt (intracrevicular method) and left in the position for 30 seconds. Strips contaminated with blood or saliva were discarded. Each sampled strip was placed into a 400µl eppendorf centrifuge tube and stored at -40C until analyzed.