A photothermal therapy-based composite hydrogel for sequential management of inflammation control and bone regeneration in severe periodontitis

Chronic periodontitis remains a global issue in oral health and it is still a significant challenge to achieve the sequential management of inflammation control and bone repair. Herein, the antibiotic levofloxacin (LF) was loaded onto PDA-modified Mxene (PDMM) 2D-composite nanosheets and embedded into the injectable hydrogel matrix of hyaluronic acid methacrylate (HAMA) to construct a 2D-nanomaterial composite hydrogel treatment platform (PDMM@LF-HAMA), which can initially control inflammation through the antibacterial effect, alleviate diffuse gingival bleeding and then promote bone regeneration with further photothermal therapy. The composite hydrogel showed mild photothermal effect under near infrared (NIR) lightand excellent photothermal conversion efficiency, which can promote cell proliferation and osteogenic differentiation in vitro. Finally, in vivo experimental periodontitis model further demonstrates that the composite hydrogel achieved inflammation control within 2 weeks. Combined with NIR (808 nm, 0.4 W/cm2), PDMM@LF-HAMA has a thicker periodontal epithelial fibrous layer and better alveolar bone height and morphology than the group without NIR after 8 weeks, while it also enhances the expression levels of OCN and Runx2. Overall, this work provides an exploratory approach for the comprehensive management of periodontitis through the whole stage.