TNFSF11 and periodontitis: Here, using a ligature-induced periodontitis model in rats 19, we evaluated whether HBOT mitigates periodontal inflammation and bone loss by integrating multiple levels of readouts: bacterial metabolites (LTA/LPS), cytokine/chemokine and adhesion programmes, cellular infiltration, RANKL/OPG expression in osteoblasts/osteocytes, and micro-CT-defined trabecular architecture.