Research progress on the role of methylation modifications in periodontitis

Periodontitis is a chronic inflammatory disease that affects the tooth-supporting tissues, and it constitutes a major global public health concern. Methylation modifications, including DNA methylation, histone methylation, and RNA m⁶A modification, represent reversible processes coordinately regulated by methyltransferases, demethylases, and binding proteins. In periodontitis, aberrant methylation modifications suppress Toll-like receptor 2 expression, leading to oral microbial dysbiosis. These modifications further disrupt normal immune regulatory functions through C-C motif chemokine ligands, Fc-γ receptor-mediated phagocytosis, and NF-κB signaling pathways, resulting in localized immune-inflammatory imbalance in periodontal tissues. In addition, various methylation modifications regulate the expression of Runt-related transcription factor 2 (RUNX2), osteoblast-specific transcription factor Osterix (OSX), and receptor activator of nuclear factor-κB ligand (RANKL), thereby interfering with osteoclast and osteoblast differentiation, disrupting bone homeostasis, and ultimately driving alveolar bone resorption. Methylation-related biomarkers demonstrate promising potential for periodontitis screening and prognostic evaluation. While numerous abnormally methylated sites have been identified in periodontitis, the precise signaling pathways and comprehensive epigenetic regulatory networks remain to be fully elucidated. This review systematically summarizes the functional roles of DNA methylation modifications in the pathogenesis of periodontitis and explores their potential value in etiological studies, diagnostic biomarker discovery, and targeted therapeutic interventions, with the aim of providing novel perspectives for periodontitis prevention and treatment strategies.