TNF and periodontitis: Ligature-induced periodontitis (LIPD) induced elevated gingival senescence biomarker expression, particularly in old mice, with a ~4-fold increase in SA-b gal (Fig. 1B and C), ~12-fold increase in p16 INK4A (Fig. 1D), ~4-fold increase in TNFa (Fig. 1E), and ~7-fold increase in IL-1β (Fig. 1F).