Abstract
OBJECTIVE: Periodontitis, a microbiome-driven chronic inflammatory disease that destroys the supporting structures of the teeth, is influenced by various environmental factors, including exposure to heavy metals such as lead and cadmium. This systematic review and meta-analysis aimed to evaluate the association between exposure to lead and cadmium and periodontitis. METHODS: A comprehensive literature search was conducted in PubMed, Web of Science, Scopus, and Embase up to February 1, 2025, following PRISMA guidelines. Observational studies examining the association between lead and/or cadmium exposure and periodontitis were included. Required clinical data were extracted, and study quality was assessed using the Newcastle-Ottawa Scale. Random-effects models were used to compute either standardized mean differences (SMD) of concentration or pooled adjusted odds ratios (aORs). Heterogeneity was assessed with I². RESULTS: Fourteen studies (13 datasets for either lead or cadmium) comprising 72,467 participants were eligible for inclusion. The meta-analysis found that cadmium and lead exposure were significantly associated with higher odds of periodontitis, with pooled aORs of 1.22 (95% CI: 1.08-1.37) and 1.85 (95% CI: 1.42-2.41), respectively. Sensitivity analyses confirmed the robustness of the findings. CONCLUSION: This study provides evidence that exposure to lead and cadmium is significantly associated with periodontitis. These findings highlight the importance of reducing environmental exposure to these heavy metals as part of preventive strategies for periodontal disease. Further research is needed to explore the underlying biological mechanisms and evaluate potential interventions to reduce exposure-associated periodontitis.