Periodontal disease in patients with thyroid diseases: a systematic review with meta-analysis

The imbalance of thyroid hormones affects the metabolic activity of various tissues, including periodontium. Also, autoimmune diseases present an increased tendency to suffer from periodontal disease. Therefore, our systematic review was designed to answer the question "Is there a relationship between thyroid diseases and periodontal disease?". Following the inclusion and exclusion criteria, 10 studies were included in this systematic review using the databases PubMed, Scopus and Web of Science (according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines). Based on the meta-analysis, patients with thyroid diseases (especially with hypothyroidism) demonstrated significantly worse periodontal status than systemically healthy controls. Moreover, according to the cross-sectional studies, 5.74% of periodontitis patients reported the concomitance of thyroid diseases. In summary, the included studies suggest a potential relationship between thyroid diseases and periodontal disease. However, further research is necessary to reliably assess the oral health in patients with hypothyroidism and hyperthyroidism.