NAMPT and periodontitis: In subgroup analysis, we confirmed the visfatin levels in patients with periodontitis were significantly higher of different sample (GCF, SMD: 4.25, 95% CI [3.00–5.49]; Serum, SMD: 7.72, 95% CI [2.36–13.08]; Salivary, SMD: 2.97, 95% CI [1.25–4.70]; Tissue, SMD: 1.00, 95% CI [0.41–1.59]).