VEGFA and periodontitis: When loading the hydrogel with 1,4‐dihydrophenonthrolin‐4‐one‐3‐carboxylic acid (1,4‐DPCA), a small molecule drug with angiogenic and bone‐forming properties by upregulating Vascular endothelial growth factor A (VEGF‐A) and Hypoxia‐inducible factor 1‐a (HIF‐1a), this hydrogel complex not only promotes CXCR4‐dependent Tregs accumulation but also facilitates alveolar bone regeneration in mice with experimental periodontitis‐induced bone loss.117, 118, 119