Cellular Senescence in Human Periodontal Tissue: A Narrative Review.

To evaluate naturally occurring cellular senescence in human gingival and periodontal ligament (PDL) tissues by addressing two questions: (1) whether susceptibility to cellular senescence increases with chronological aging, and (2) whether periodontitis lesions exhibit senescence-associated features indicative of inflammation-accelerated senescence. A structured search of PubMed and bioRxiv databases identified 186 articles. After applying the inclusion criteria, 13 studies that investigated senescence markers in gingival and PDL tissues in the context of aging or periodontitis were selected. We observed tissue-specific senescence. Gingival fibroblasts exhibited progressive age-related senescence. In contrast, PDL fibroblasts showed consistently high baseline senescence regardless of age, whereas PDL stem cells exhibited age-related decline in regenerative potential. In periodontitis-affected tissues, senescence markers-such as p16, SA-β-gal, and SASP-related factors-were elevated compared to healthy tissues, even among younger individuals. Senescence is a key biological feature of periodontal tissues with distinct cell-type-specific dynamics. These findings suggest that aging and inflammation contribute to the accumulation of senescent cells, which may influence periodontal health and disease progression.