Construction of PDA@Ag-Coated Gutta-Percha for Root Canal Therapy

Root canal therapy is currently the leading treatment method for endodontic and periapical diseases. Gutta-percha (GP), the most widely used root canal filling material, is inert and biocompatible; however, it suffers from the lack of antibacterial properties, and the root canal system is likely to become reinfected. Enterococcus faecalis is one of the primary pathogens of bacterial reinfection in root canals. Herein, silver ions were reduced to silver nanoparticles using polydopamine to modify the surface of the gutta-percha, thereby forming antibacterial gutta-percha and thus filling the root canal. Results obtained through in vitro experimental procedures indicated that the combined application of GP@PDA@Ag and 808 nm near-infrared (NIR) irradiation could eliminate planktonic E. faecalis and prevent the formation of E. faecalis biofilms through inhibiting the expression of the cylA, esp, and gelE genes. In addition, the infected root canal model showed that the combined use of GP@PDA@Ag and 808 nm NIR irradiation inhibited the proliferation of E. faecalis inside the root canal and improved the prognosis of endodontic periapical disease. Meanwhile, GP@PDA@Ag also has good biocompatibility. In brief, the application of the 808 nm NIR-irradiated PDA@Ag-coated gutta-percha introduces a potent new option for root canal filling. This approach is designed to counteract the bacterial infection microenvironment within root canals, thereby enhancing the success rate of root canal therapy.