TNF and rheumatoid arthritis: The results of this study revealed that further studies should examine patients with AS or RA with a complete dataset, including data on their treatment and medication (i.e. vitamin D levels and use of anti-TNF-α, IL-6R antagonists, methotrexate etc.), clinical oral examination (i.e. source of infection, pain, vitality of involved tooth, percussion/palpation sensitivity and history of dental treatment) and radiological examination (i.e. presence and types of lesions).