IL6 and periodontitis: Elevations of interleukins (IL)‐1β, IL‐6, TNF‐α, and matrix metalloproteinases (MMPs) were identified in periodontitis and hold great potential as biomarkers of diagnosis for this disease.[45, 46, 52, 55] IL‐6, IL‐8, and TNF‐α have exhibited an area under the curve (AUC) greater than 0.8 for the diagnosis of oral squamous cell carcinoma compared with controls.[73] Other reports have suggested a correlation between cytokines and systemic diseases.