In patients with chronic periodontitis, bacteria can alter histone modifications in periodontal tissue and activate a series of inflammatory and bone metabolism-related signaling pathways.80,81 Lipopolysaccharide (LPS) has been identified as a pivotal periodontal pathogenic factor, capable of activating NF-κB signaling and promoting the release of inflammatory cytokines such as IL-6 and IL-8. This evidence concerns the gene NFKB1 and periodontitis.