P2RX5 and periodontal disorder: In our study group, it is observed how PD+IR+ patients show an up-regulation of P2RX5 (FD = 1.29; p = 0.0377), which could explain the clinical condition of active periodontal disease and implant failure in this group of patients, despite showing down-regulation of IL1B, since the study by Kim et al. 2018 showed in an in vivo model of how P2RX5-deficient mice were protected against LPS-induced inflammatory bone loss.