Downregulation of the expression levels of osteoclast marker genes Acp5, Nfatc1 and Mmp9 induced by RANKL to inhibit osteoclast formation, and downregulating the expression levels of inflammatory cytokines such as IL-1β, IL-6, and IL-8 in LPS-induced HGFs. Inhibiting alveolar bone resorption and destruction in mice models of periodontitis. Here, MMP9 is linked to periodontitis.