Although RA pathomechanisms remains incompletely understood, periodontitis and RA share pathogenic features : genetic and environmental influences, chronic inflammatory disease, immunoregulatory imbalance, bacterial factors, persistence of antigen/peptide and clinical factors (conjunctive and hard tissues destruction). Several hypothesis can be evocated : Gram negative bacterial systemic spreading, inflammatory transmitter substance systemic spreading (IL1, IL6, IL17, PGE2), systemic spreading of bacterial degradation products (LPS for example).

Currently Porphyromonas gingivalis (PG) might be a susceptibility factor to RA because PG has an enzyme, the peptidylarginine deiminase leading to auto antibodies creation and RA increasing. As periodontitis, RA is chronic disease with a cyclic increase evolution, needing a complex pluridisciplinary treatment approach. Recent studies have reported an increased prevalence of RA patients with periodontal disease. Others studies show that periodontal treatment induces a significant decrease of the sedimentation rate and of the DAS28. Periodontitis is suspected to be an independent, aggravating factor in patients with RA (given the definition from NIH : an aggravating factor is something that makes a condition worse). So periodontal treatment cannot be considered as a RA treatment per se. But it is hypothesised that treating periodontitis in RA patients showing signs of periodontitis could result in improvement in RA disease activity. To date the role of periodontitis as an aggravating factor in these patients remains unclear, and only RCT designs can reasonably be used to test this causal hypothesis. There still remains some RA patients who have persistent symptoms and frequent exacerbations despite specialist care and continuous treatment, so results of treating aggravating factors are needed. As the majority of patients will benefit from a systematic evaluation and treatment of aggravating factors, the periodontal treatment strategy need to be tested.

The aim of this randomised controlled trial is to assess the effectiveness of periodontal treatment for rheumatoid arthritis patients.

To assess the effectiveness of periodontal treatment to reduce the severity of rheumatoid arthritis (RA), in patients suffering from both periodontitis and rheumatoid arthritis. The hypothesis is that periodontal treatment reduce the severity of rheumatoid arthritis.

INCLUSION CRITERIA:

• rheumatoid arthritis diagnosed for at least one year
• DAS28 score between 3.2 and 5.1
• no change to medication, dosage or formulation in RA treatment during the 3 months preceding the screening visit
• subject available for all study visits over three months in the Dental Care Departments (V1 to V4)
• subjects with at least six natural teeth with root
• subject with periodontitis, defined by the presence of one site with periodontal probing depth ≥ 4 mm and clinical attachment level ≥ 3 mm on at least 4 teeth.
• subject has given his informed consent: 1 week cooling-off period

EXCLUSION CRITERIA:

• subject will not qualify for enrolment if he presents at least one of the following: acute oral infection, acute oral pain (including pulpitis), suspicious oral mucosal lesion, severe oral inflammation unrelated to periodontal conditions, or need for immediate tooth extractions
• have a planned hospitalization within 4 months after the screening visit
• subject suffering from one or more known infectious diseases (HIV, hepatitis, infectious mononucleosis),
• subject suffering from known clinically significant renal disease (creatinine clearance <60 ml/min), or liver disease,
• unbalanced diabetes
• have a known risk of endocarditis,
• have a permanent pacemaker,
• subject taking antithrombotic treatment,
• subject having severe difficulties in understanding written and spoken French
• for females: are pregnant or intending to become pregnant, or lactating
• subject suffering from a chronic disorder that requires chronic or intermittent use of antibiotics,
• subject having known hypersensitivity to chlorhexidine gluconate
• are participating in another intervention study
• have known contraindications to both amoxicillin and clindamycin
• have known contraindications to dental local anesthetic.