Abstract
Persistent apical periodontitis (PAP) is characterized by periapical inflammation and alveolar bone resorption resulting from microorganisms that are resistant to conventional root canal disinfection. The treatment goals for PAP are to effectively eliminate resistant microorganisms and inhibit bone resorption. Root canal therapy (RCT) is the primary treatment for PAP, with chemical disinfection being a fundamental step in the process. This study developed Fe3O4‒MXene, a new root canal disinfectant with photothermally induced antibacterial properties and the potential to inhibit bone resorption. Under 808 nm light, Fe3O4‒MXene demonstrated high performance in converting the light energy into heat, effectively inhibiting Enterococcus faecalis (E. faecalis) biofilms. Additionally, Fe3O4‒MXene-mediated photothermal therapy enhanced the ability of NaOCl to eliminate E. faecalis contamination from the root canal system. Furthermore, magnetically guided to periapical areas, Fe3O4‒MXene suppressed osteoclast differentiation and function by neutralizing intracellular reactive oxygen species, downregulating NF-κB and NFATc1 pathways, which are critical regulators of osteoclast differentiation. In conclusion, Fe3O4‒MXene is a promising new root canal disinfectant that may improve PAP outcomes by simultaneously targeting root canal infection and alveolar bone resorption.