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. <i>In vitro</i> 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. <i>In vivo</i> 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.