Injectable Multifunctional Hydrogel Loaded With EGCG-Cu Complexes For Periodontitis

Aim or purpose: This study aims to develop an injectable Laponite/gelatin hydrogel loaded with epigallocatechin gallate (EGCG)-copper ion (Cu²⁺) complexes as a localized therapy for periodontitis, addressing the limitations of conventional treatments in pathogen eradication, antibiotic resistance, inflammation and oxidative stress control, and tissue regeneration. Materials and methods: Cu²+ coordination was utilized to enhance the stability, antioxidant capacity, and antimicrobial efficacy of EGCG. A Laponite/gelatin hydrogel was designed for controlled EGCG-Cu release, while bioactive ions (Li⁺, Mg²⁺, Si⁴⁺) from Laponite promoted osteogenesis and periodontal tissue regeneration. In vitro and in vivo experiments were conducted to evaluate the hydrogel’s biocompatibility, antibacterial activity against Porphyromonas gingivalis, induction of M1-to-M2 macrophage polarization, and periodontal tissue regeneration effects. Results: The hydrogel demonstrated excellent biocompatibility, effectively inhibited Porphyromonas gingivalis, promoted M1-to-M2 macrophage polarization, and significantly facilitated periodontal tissue regeneration. Conclusions: This study presents a Laponite/gelatin hydrogel-based localized therapeutic strategy that enhances EGCG stability and bioactivity, effectively inhibits periodontal pathogens, modulates immune responses, and promotes periodontal tissue repair, providing new insights for periodontitis treatment.