TNFRSF11B and major depressive disorder: RANKL levels and the RANKL/OPG ratio were significantly higher in patients with periodontitis and increased with disease severity (p ≤ 0.05), while OPG showed no significant change.<h4>Conclusion</h4>Periodontitis and its severity significantly influence salivary RANKL and the RANKL/OPG ratio, while depression does not.