The Impact of Heavy Metal Contamination in Humans and Periodontitis: A Scoping Review.

Periodontal disease, one of the most prevalent diseases worldwide, is a chronic inflammatory disease caused by dysbiotic dental biofilms that trigger the host's immune response. Periodontitis is a type of periodontal disease characterized by the destruction of tissues that support the teeth. The disease is influenced by various systemic and environmental risk factors. As heavy metals have been associated with the development of chronic inflammatory diseases, the present scoping review aimed to determine the coverage of the literature on whether human contamination by heavy metals affects periodontitis, as well as their mechanisms of action. Eight studies were selected, and two reviewers evaluated them. Most studies were cross-sectional studies involving humans and one study was performed on rats. Our review revealed a significant correlation between periodontitis and bioaccumulation of lead and cadmium. Oxidative stress generated by trace metals, characterized by elevated levels of reactive oxygen species, causes tissue damage through lipid peroxidation, enzymatic oxidation, and stimulation of proinflammatory cytokines. In conclusion, heavy metals contamination may be a risk factor for the development of periodontitis. Oxidative stress factors seem to increase the extent of the inflammatory response.