Porphyromonas gingivalis is associated with the production of citrullinated proteins and with the development of RA [6], as well as the expansion of Th17 cells and the signaling of IL-17’s receptor A, which promotes the infiltration of neutrophils in the joints, and the increase of IL-17 and TNF-α [39]. This evidence concerns the gene IL17A and rheumatoid arthritis.