Calcium hydroxyapatite @ polydopamine core-shell microspheres for photothermal regulation of human gingival fibroblast behavior

Gingival recession, a common oral problem, often results in functional complications and aesthetic imperfections. Calcium hydroxyapatite (HA) microspheres, known for their fibroblast-activating properties, have been used for facial tissue augmentation. The photothermal conversion effect, which uses near-infrared (NIR) light to generate mild thermal stimuli, has been shown to enhance cellular activity and accelerate wound healing. In the current study, core-shell structured calcium hydroxyapatite @ polydopamine (HA@PDA) microspheres with biocompatibility and photothermal efficacy were synthesized to improve the treatment of gingival recession. Cellular experiments demonstrated that the behavior of human gingival fibroblasts (HGFs) and the polarization of macrophages are modulated by HA@PDA microspheres through photothermal conversion under 808 nm NIR irradiation. The implications of these findings suggest that photothermal HA@PDA microspheres may serve as a promising modality for gingival augmentation, offering a safe, non-invasive, effective, and sustainable treatment strategy.