CHRNA7 and periodontitis: This finding is in accordance with the results in degenerative diseases in the central nervous system.19 Up‐regulated expression of amyloid β can suppress expression of phosphorylated GSK‐3β, leading to decreased expression and diminished function of α7 nAChR.39, 40 Thus, we speculated that in smoking‐related periodontitis, decreasing phosphorylation of GSK‐3β should be an effective therapy.