Aim: A prospective randomized, controlled clinical trial comparing two groups of a cohort of Rheumatoid Arthritis (RA) patients with periodontal disease will be carried out to identify if the effect of non-surgical periodontal therapy is a predictor of remission/ low disease activity (LDA)-remission.

Methods: 42 patients with RA and periodontitis from the RA Almenara cohort will be included (ACR 1987 and or ACR/EULAR 2010 criteria with more than 16 years old at diagnosis); those with <6 teeth, current infections, cancer or oral precancerous lesions, diabetics, Sjogren's syndrome, use of antibiotics or drugs associated with dry mouth and dental surgery, will be excluded. Periodontal Disease was defined by the presence of periodontitis stage 3 or 4 with at least 2 non-adjacent teeth with insertion loss >=5mm, probing depth >=5mm and bleeding on probing according with the 2018 periodontitis diagnostic criteria.

Two RA patients groups will be follow up by monthly visits. Patients will be divided into two groups (intervention and no intervention treatment). PD treatment will be performed by a qualified periodontist. No intervention group will receive PD treatment after 6 month visit because ethical principles. Disease activity will be determined according with DAS 28index, Clinical Disease Activity Index (CDAI) and Simple Disease Activity Index (SDAI) scores, C-reactive protein (CRP), the erythrocyte sedimentation rate (ESR), and rheumatoid factor levels will be registered before and after PD treatment (baseline, 3 and 6 months visits), and the differences between the groups will be analyzed and compared. Periodontal parameters including probing depth (PD), clinical attachment loss, and sulcus bleeding index (SBI) will be correlated with the factor levels.

Inclusion Criteria:

• Patients of both sexes
• Age ≥16 years at the time of diagnosis and who do not meet criteria of overlap with any other autoimmune disease.
• Presence of six or more permanent teeth in the mouth, excluding third molars.
• Presence of periodontitis stage 3 or 4 with at least 2 non-adjacent teeth with insertion loss >=5mm, probing depth >=5mm and bleeding on probing according to Tonetti et al.[35].
• Willingness to attend all visits for the duration of the study.

Exclusion Criteria:

• Patients with Sjogren's syndrome

  • - Severe ongoing systemic infection.
  • - Associated dental infection
  • - History of oral cavity cancer or precancerous lesion.
  • - Use of local or systemic antibiotics in the last 3 months (including tetracyclines or other medication that could change the periodontal evaluation in the investigator's opinion, such as heparin alendronate, antivitamin K).
  • - Medications that induce gingival hyperplasia (such as phenytoin, warfarin or cyclosporine).
  • - Pregnant or breastfeeding women
  • - Participation in another intervention study.
  • Patients with a history of PD treatment in the last 6 months or previous dental surgery)