CRP and periodontitis: Studies have shown a higher neutrophil–lymphocyte ratio (NLR), a lower lymphocyte-monocyte ratio (LMR) [14], increased levels of proinflammatory cytokines such as interleukin 17 (IL‐17) [21, 23], C-reactive protein (CRP), and fibrinogen in patients with periodontitis compared to healthy controls [24, 25].