Flowable Oxygen-Release Hydrogel Inhibits Bacteria and Treats Periodontitis

Periodontitis, the chronic inflammation of the periodontal tissues caused by bacteria in plaque, is the leading cause of tooth loss in adults in the world. Currently, periodontitis is effectively treated with mechanical cleaning and the use of antibiotics. However, these treatments only temporarily remove plaque, which can rapidly proliferate and multiply in periodontal pockets over time. Although antibiotics have positive antimicrobial effects, their long-term use increases the risk of the emergence of drug-resistant strains. The emergence of resistant strains reduces the effectiveness of periodontitis treatment and makes the disease more difficult to control. Herein, this paper reports the development of an injectable self-oxygenating composite hydrogel for periodontal therapy, which was produced by loading CaO2 nanoparticles and ascorbic acid into an injectable alginate hydrogel. CaO2 can improve the periodontal pocket microenvironment by reacting with water to generate oxygen, calcium ions can be used as a bone regeneration material, and ascorbic acid protects cells. The authors further showed that the composite hydrogel inhibited growth and colonization of anaerobic bacteria, reduced the degree of inflammation, and promoted alveolar bone regeneration. In conclusion, these findings suggest that the composite hydrogel can be used as a biocompatible, convenient, and effective method for periodontitis treatment.