Dopamine Carbon Dots Synergize with Mild Photothermal Therapy for Anti-Inflammatory Treatment of Periodontitis

Periodontitis is a chronic inflammatory oral disease characterized by dysregulated host immune responses. Modulating the immune microenvironment has emerged as a promising therapeutic strategy to address the limitations of conventional treatments. To explore this approach, we developed uniformly sized dopamine-derived carbon dots (DACDs) with smooth surfaces via hydrothermal synthesis using dopamine as the precursor. The synthesized DACDs exhibited favorable biosafety and considerable photothermal conversion capability. In vitro experiments employing quantitative real-time PCR (qRT-PCR), Western blotting, and immunofluorescence staining demonstrated that DACDs synergized with mild photothermal therapy (MPTT) to significantly downregulate pro-inflammatory cytokine expression in RAW264.7 cells. In vivo studies further confirmed that the combined application of DACDs and MPTT markedly reduced periodontal inflammation and attenuated alveolar bone resorption, as evidenced by Micro-CT analysis and histological staining. Collectively, DACDs mitigate bone destruction by suppressing inflammatory cascades, establishing a novel and effective immunomodulatory strategy for the management of periodontitis.