This study aimed to evaluate and compare demographic, periodontal, and cardiac parameters; Dickkopf-3 (DKK-3; rs11544817) and complement factor H (CFH; rs10737680) protein levels; and gene expression in patients with periodontitis with and without coronary artery disease (CAD) at baseline and following non-surgical periodontal therapy (NSPT). The gene discussed is DKK3; the disease is coronary artery disorder.