Background: Rheumatoid arthritis (RA) and periodontitis are both chronic inflammatory disease which demonstrate similarities in terms of mechanism, histopathology and demography. An association between these conditions has been demonstrated previously but has been called into question more recently.Methods: The published databases MEDLINE, EMBASE and PsycINFO were searched using search terms related to RA and periodontitis. Articles were selected if they included data on the number of people with RA diagnosed with periodontitis (or periodontal disease parameters) compared to a control comparison group. Review articles, case reports, animal model studies, non-English language and articles with unavailable abstracts were excluded. Data was extracted, critically appraised using the Downs and Black tool and a random effect Mantel-Haenszel meta-analysis was performed.Results: 21 papers met the eligibility criteria and provided data for the meta-analysis; 17 studies (including a total of 153,492 participants) comparing RA to healthy controls and 4 (including a total of 1378 participants) comparing RA to osteoarthritis (OA). There was a significantly increased risk of periodontitis in people with RA compared to healthy controls (RR: 1.13; 95% CI: 1.04, 1.23; p=0.006; N: 153,277) with a significantly raised mean probing depth, risk of bleeding on probing (BOP) and absolute value of clinical attachment loss in those with rheumatoid arthritis. When comparing RA and OA, there was no significant difference in the prevalence of periodontitis, however the risk of BOP was greater in OA than RA.Conclusion: The significant association between RA and periodontitis is supported by the results of our systematic review and meta-analysis of studies comparing RA to healthy controls. In our meta-analysis, however, this is not replicated when comparing RA to OA controls.