As a suppressive subset of T cells, Tregs express TGF-β and other protective anti-inflammatory cytokines to mediate the overactivation of Th17 cells, limit injury to inflamed tissue and facilitate repair.53 In this context, a Th17 cell/Treg imbalance has been reported in periodontitis patients,71 and a number of researchers, such as Elashiry52 et al., have found that periodontitis can be alleviated by shifting the Th17 cell/Treg balance, indicating that the this balance contributes to maintaining periodontal homeostasis. Here, TGFB1 is linked to periodontitis.