Antibacterial and Antioxidant GelMA/CeO ₂ Hydrogel Promotes Oral Mucosal Healing

Oral mucosal wounds can greatly affect overall patient health and interfere with eating and speech functions. The intraoral environment provides an ideal milieu for bacterial growth and proliferation, thereby increasing the risk of infection in oral mucosal wounds. In the event of wound infection, immune cells undergo a respiratory burst, leading to the production of a substantial amount of reactive oxygen species. Bacterial colonization and excessive reactive oxygen species can induce adverse inflammatory responses, resulting in delayed healing of oral mucosal wounds. Cerium oxide (CeO₂) nanoparticles were chosen for their high antibacterial and antioxidant capacities. Gelatin methacrylate (GelMA) is an excellent carrier of CeO₂ nanoparticles, which has good injectivity after precrosslinking and is suitable for deep oral wounds. In this study, GelMA/CeO₂ hydrogels with antibacterial and antioxidant functionalities were engineered to enhance the healing of oral mucosal wounds. The GelMA/CeO₂ hydrogels demonstrated excellent biocompatibility, promoted gingival fibroblast migration, and upregulated the expression of genes involved in wound healing. In addition to their significant antioxidant activity, the GelMA/CeO₂ hydrogels exhibited strong antibacterial properties, as evidenced by the inhibition of <i>Streptococcus mutans</i> and <i>Porphyromonas gingivalis</i> growth. The GelMA/CeO₂ hydrogels also significantly accelerated the healing of infected mucosal wounds in a rabbit model, achieving a 100% wound closure rate by day 7. In summary, the use of these novel GelMA/CeO₂ hydrogels represents an effective strategy for the treatment of oral wounds.