Background/Objectives: The aim of this systematic review and meta-analysis was to determine the association between rheumatoid arthritis and periodontal disease. Methods: This systematic review and meta-analysis of the scientific literature was carried out based on the recommendations of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We analyzed all studies that evaluated the relationship between the chronic inflammatory diseases through the response to non-surgical periodontal treatment, comparing the values of CAL (Clinical Attachment Level) for PD (periodontal disease) and DAS28 for RA. A total of three databases were searched in the literature search: Pubmed, Scopus, and Web of Science. After eliminating duplicate articles and applying certain inclusion criteria, of the 29 articles found, a total of 6 were included in the present study. Results: A statistically significant difference in mean reduction of -0.56 mm was obtained for CAL, with a 95% confidence interval of the difference between -0.82 and -0.31 (z-test = -4.33; p-value = 0.001) in favor of the periodontal treatment group. The heterogeneity of the meta-analysis was slight (I2 = 39% and Q = 8.19; p-value = 0.146). For DAS28, treatment showed a mean reduction of -0.39 DAS points, with a 95% CI between -0.46 and -0.31 (z-test = -10.3; p-value < 0.001) among patients with PD and RA. Conclusions: The present study shows how the control of periodontal disease through non-surgical periodontal treatment can reduce the severity of RA. This finding consistently supports the idea that there is a pathogenic association between these two chronic inflammatory diseases.
Keywords: autoimmune; autoimmune disease; periodontal disease; periodontitis; rheumatoid arthritis.