Stroke remains one of the major global causes of disability and death, and persistent inflammatory disorders can promote atherosclerosis, thereby increasing the likelihood of stroke. This systematic review and meta-analysis aimed to evaluate the relationship between periodontal diseases—specifically periodontitis and gingivitis—and the occurrence of stroke. A comprehensive literature search was carried out in PubMed, Ovid EMBASE, Ovid MEDLINE, Web of Science, Cochrane CENTRAL, Science Citation Index, DARE, and several clinical trial registries for studies published up to February 2022. Two independent reviewers extracted the data, and meta-analysis was performed using Stata version 13. Thirteen studies identified a link between stroke and periodontitis, as measured by clinical attachment loss (CAL), while six studies demonstrated an association between stroke and gingivitis, assessed using the gingival index (GI). Five of the gingivitis studies also examined CAL, resulting in a total of 14 studies being included in the meta-analysis, encompassing 35,937 participants aged 17 years and older. A significant relationship was observed between both periodontal conditions and all stroke subtypes. Specifically, periodontitis showed a significant association with stroke across 13 studies (effect size [ES]: 1.32; 95% confidence interval [CI]: 1.04–1.60), and gingivitis demonstrated a similar trend across six studies (ES: 1.17; 95% CI: 0.42–1.92). The evidence from this systematic review and meta-analysis supports a notable correlation between stroke and periodontal disease across case–control, cohort, and cross-sectional designs. However, further large-scale, prospective cohort studies are required to confirm these findings and clarify the causal relationship.
