IL6 and neurodegenerative disease: Notably, several researches have declared the linkage between periodontitis and inflammation: Leira et al. demonstrated that severity of periodontitis was associated with elevated degree of hs-CRP and IL-6 in a case-control study of neurodegenerative diseases [26]; Gomes-Filho et al. found increasing level of CRP in participants with periodontitis, who may have higher risk of acute myocardial infarction [27].