A Comprehensive Analysis of the Association between Thyroid Dysfunctions and Periodontal Health: Systematic Review

The purpose of this systematic literature review was to establish a correlation between thyroid dysfunctions and periodontium health.

The systematic review was conducted according to PRISMA statement. An electronic search was performed using MEDLINE (PubMed) and Google Scholar databases using a combination of keywords "hypothyroidism", "hypothyroidism", "thyroid", "thyroid dysfunction" and "periodontitis". The research covered the period from January 1, 2019 and July 1, 2024, included studies written in English, conducted in humans.

The results showed that hyperthyroidism can be associated with a higher prevalence of periodontitis due to decreased oral microbiome diversity, serum thyroid-stimulating hormone levels, increased periodontal pocket depth, clinical attachment loss and interleukin-6. Hyperparathyroidism after parathyroidectomy may lead to a slightly higher risk of tooth extraction in the first two years afterward because decreasing lamina dura, increasing periodontal ligament width. And hypothyroidism negatively affects the homeostasis of calcium and phosphorus in the oral fluid and can change the composition of bone minerals.

Hyperthyroidism increases the risk of periodontitis by promoting deeper periodontal pockets, reducing oral microbiome diversity, altering alveolar bone structure and elevating inflammatory markers like interleukin-6, which are linked to disease progression. Hypothyroidism worsens periodontal disease by disrupting calcium-phosphorus balance and causing alveolar bone changes, especially in young individuals. Both conditions affect periodontal homeostasis, emphasizing the bidirectional relationship between endocrine and periodontal health. Dentists should monitor thyroid dysfunction, as managing thyroid levels may improve periodontal treatment.