Saliva and serum samples obtained for each patient were used for cytokine analysis. Prepared samples were analyzed for Lipoxin A4 (LXA4), Caspase 8 (CASP8) and Sirtuin-6 (SIRT6) using commercial ELISA kits

(Elabscience, Houston, Texas, USA and Bioaasay Technology Laboratory (BT-Lab), Shanghai, China, respectively) according to the manufacturer's instructions. The detection limits of ELISA kits were 0.78 - 50ng/ml for LXA4, 0.16 - 10ng/ml for CASP8 and 0.1- 40 ng/ml for SIRT6.

Saliva were collected to analyze the selected markers as unstimulated samples during the early hours of the day. The saliva was centrifuged and then transferred into Eppendorf tubes.

Venous puncture was performed after saliva collection and 10 mL of blood samples were collected by qualified staff (MFD) from each participant. Saliva and serum were then stored at -80 °C until analysis.

Measurement of the depth of a sulcus or periodontal pocket determined by measuring distance from a gingival margin to the base of the sulcus or pocket with a calibrated periodontal probe.

Clinical attachment level (or loss, CAL) is a more accurate indicator of the periodontal support around a tooth than probing depth alone. CAL is measured from a fixed point on the tooth that does not change, the CEJ.

To calculate CAL, two measurements are needed: distance from the gingival margin to the CEJ and probing depth.

In recession: probing depth (+) gingival margin to the CEJ (add). In tissue overgrowth: probing depth (-) gingival margin to the CEJ (subtract)

referring to bleeding that is induced by gentle manipulation of the tissue at the depth of the gingival sulcus, or interface between the gingiva and a tooth.

Saliva and serum samples obtained for each patient were used for cytokine analysis. Prepared samples were analyzed for Lipoxin A4 (LXA4), Caspase 8 (CASP8) and Sirtuin-6 (SIRT6) using commercial ELISA kits

(Elabscience, Houston, Texas, USA and Bioaasay Technology Laboratory (BT-Lab), Shanghai, China, respectively) according to the manufacturer's instructions.