A recent clinical study reported high levels of salivary resistin (14.45 ± 1.88 ng/ml) in normal-weight patients with chronic periodontitis compared to those with gingivitis (11.59 ± 1.6 ng/ml) and periodontally healthy cases (6.43 ± 0.81 ng/ml) [10]. This evidence concerns the gene RETN and gingivitis.