This study aimed to evaluate salivary concentrations of Receptor Activator of Nuclear Factor Kappa-B Ligand (RANKL) and Osteoprotegerin (OPG)-key regulators of osteoclast activity and periodontal bone resorption-in patients with periodontitis and depression.<h4>Materials and methods</h4>In this cross-sectional study, 80 patients from Shahid Beheshti University Dental School were categorized into four groups based on the presence or absence of periodontitis and depression. This evidence concerns the gene TNFSF11 and depressive disorder.