Hussain SB, Botelho J, Machado V, et al. - A systematic review and meta-analysis was conducted to evaluate the evidence on the relationship between rheumatoid arthritis (RA) and periodontitis (PD) in terms of clinical and laboratory outcomes. The two independent reviewers conducted an electronic search of several databases (PubMed, EMBASE, MEDLINE, LILACS, CINHL, Scopus, Web of Science, The Cochrane Library, OpenGrey, and Google Scholar) up to March 2019 (PROSPERO CRD42018107817). A sum of 8 case-control studies were distinguished after the final search of 1,491 titles. They applied Random-effects models for quantitative analyses. The data indicated that PD is correlated with worse RA clinical activity as evaluated by DAS28 scores whereas, RA individuals do not have worsen PD clinical outcomes.