Periodontal disease severity in subjects with dementia: A systematic review and meta-analysis

•Periodontal disease and dementia are common diseases in the older adults.•14 articles meeting our inclusion criteria in the systematic review.•The meta-analysis was conducted with 4 articles.•Dementia patients seemed to present worsened periodontal conditions. Despite clinical trials and reviews attempt to assess a possible relationship between dementia and periodontal disease, no meta-analysis has been performed and this issue remains undetermined. The aim of this study is to conduct a systematic review and meta-analysis to assess severity of periodontitis in subjects with dementia. The search was conducted in Pubmed, Embase/MEDLINE. Two independent reviewers extracted data and assessed the risk bias (Newcastle–Ottawa scale). Meta-analyses were performed using the means of probing depth (PD) and clinical attachment loss (CAL) in patients with or without dementia. The mean difference were analyzed (P ≤ 0.05). Fourteen studies were included in the systematic review. In the qualitative analysis, most studies reported higher prevalence of periodontal disease in dementia patients. The studies had low risk of bias and two meta-analyses were performed for each parameter, including or not a cross-sectional study. The meta-analyses including the cross-sectional study demonstrated significant association between dementia and periodontal disease (mean difference: PD = 1.41; CAL = 1.40, P