There were inconclusive results as to levels of interleukin‐1β (IL‐1β) in periodontitis in RA as summarized from several cross‐sectional studies, and the same levels of interleukin‐4 (IL‐4) and interleukin‐10 (IL‐10) between RA patients, periodontitis, and periodontally healthy patients.8, 9. This evidence concerns the gene IL4 and periodontitis.