Understanding resolution of inflammation in periodontal diseases: Is chronic inflammatory periodontitis a failure to resolve?

Periodontitis is an infectious-inflammatory disease that results from loss of balance between the commensal microbiome and the host response. The hyper-inflammatory, uncontrolled inflammatory immune lesion promotes tissue damage and impedes effective bacterial clearance. In this review, the relationship between the microbiome and the inflammatory/immune response is explored in the context of a bi-directional pathogenesis; bacteria induce inflammation and inflammation modifies the growth environment causing shifts in the composition of the microbiome. Resolution of inflammation is an active, receptor-mediated process induced by specialized pro-resolving lipid mediators. Inflammatory disease may, therefore, be the result of failure of resolution. Failure to resolve inflammation coupled with resultant microbiome changes is hypothesized to drive development of periodontitis. Re-establishment of microbiome/host homeostasis by specialized pro-resolving lipid mediator therapy suggests that microbiome dysbiosis, the host hyperinflammatory phenotype, and periodontitis can be reversed.