TNF and oral lichen planus: For instance, salivary levels of tumor necrosis factor α (TNF-α), IL-1, IL-4, IL-6, and IL-8 have been described as relevant biomarkers for oral lichen planus diagnosis and prognosis.8 Also, IL-1β, TNF-α, IL-6, and the receptor activator of nuclear factor κB ligand (RANKL), among other cytokines, are known to be involved in immune response regulation in periodontal diseases.9