TNF and rheumatoid arthritis: The RA+periodontitis group received medication with corticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs), and conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) but not with any biological DMARDs (bDMARDs), including inhibitors of tumor necrosis factor, interleukin-6 receptor, and the co-stimulatory signal for T cell activation (Table 1).