LEP and periodontitis: Following 4 weeks of therapy, TNF-α correlations intensified markedly with leptin (ρ = 0.671, P < 0.01), resistin (ρ = 0.619, P < 0.01), and periodontal indices (gingival bleeding index: ρ = 0.245; periodontitis grading: ρ = 0.331; P < 0.01).