Recent Advances in Injectable Hydrogel Biotherapeutics for Regenerative Dental Medicine

Dental caries and periodontitis continue to be significant oral health challenges. Traditional therapies typically manage infection and inflammation but seldom restore lost tissue. In this way, injectable hydrogels have emerged as versatile biomaterials that adapt to the complex anatomy of the dentin-pulp complex and periodontal lesions. Generally speaking, by incorporating antimicrobial, anti-inflammatory, and pro-regenerative cues, these hydrogels support localized disinfection, promote angiogenesis, and foster tissue regeneration. More specifically, recent advances in functionalizing hydrogels with growth factors, bioactive compounds, and dentin matrix components have effectively modulated inflammatory responses, stimulated host cell activity, and facilitated the formation of hard and soft tissue for regenerative endodontic therapies. In periodontology, engineered hydrogels have demonstrated their ability to deliver osteogenic, antimicrobial, and immunomodulatory agents while also enabling the encapsulation of stem cells or extracellular vesicles, thereby enhancing cellular activity and supporting the regeneration of alveolar bone and soft tissue. This review summarizes recent advancements in injectable hydrogels for regenerating the dentin-pulp complex and periodontal tissues, discussing their design principles, performance, and future directions. Although not exhaustive, it provides a comprehensive overview to inspire further research and innovation, encouraging the development of novel, easy-to-apply, and highly biocompatible multifunctional hydrogels for regenerative dental medicine.