Injectable Thermosensitive Gel Loaded Salvianolic Acid B Alleviates Periodontitis by Down‐Regulating Oxidative Stress and Protecting Mitochondrial Function

ABSTRACT Periodontitis is an immune‐reactive disease characterized by excessive inflammation and oxidative stress (OS). Salvianolic acid B (Sal B) is a component isolated from the root of Salvia miltiorrhiza , known for its strong anti‐inflammatory and antioxidant effects. Our study examined the beneficial effects of Sal B on OS and mitochondrial function (MF) in periodontitis, as well as its potential mechanisms. In vitro experiments demonstrated that Sal B can reduce the inflammatory response in periodontal tissue cells and eliminate oxidative stress products such as reactive oxygen species (ROS). Furthermore, Sal B enhances mitochondrial membrane potential (MMP) and increases adenosine triphosphate (ATP) production. We designed a methacryloylated glycol chitosan/β‐glycerophosphate composite hydrogel (MAGC/β‐GP Gel) for the localized delivery of Sal B. Sal B@MAGC/β‐GP gel is stable and exhibits good thermal sensitivity, allowing for continuous release of Sal B in the periodontal pocket. Results from a mouse model of periodontitis showed that Sal B@MAGC/β‐GP gel significantly reduces alveolar bone absorption, eliminates ROS, increases MMP levels, and alleviates periodontal inflammation. Overall, this study demonstrates that Sal B has potential as an antioxidant therapeutic agent for periodontitis, and the novel Sal B@MAGC/β‐GP gel composite material is expected to be used for intrapocket injections in clinical settings.