α7 nAChR is a classical receptor that plays a role in the physiological regulation of neurons.31 After identifying its expression in oral tissues,32 α7 nAChR was considered a critical molecular regulatory target of oral diseases.14 This study further suggests that α7 nAChR expression levels varied in periodontal tissues derived from different microenvironments (Figure 3). Here, CHRNA7 is linked to mouth disorder.