Schematic illustration of injectable hydrogels in periodontitis treatment.

Pathogenic microorganisms pose significant threat to global health. In particular, conventional antibiotic treatments run the risk of exacerbating bacterial resistance. Antimicrobial sonodynamic therapy (aSDT), which combines sonosensitizers and low-intensity ultrasound (US), has opened up new avenues for treating drug-resistant bacteria. The appeal of this therapy lies in its ability to focus US energy toward the deep-seated site of bacterial infection sites, which it locally activates sonosensitizers and generates cytotoxic reactive oxygen species (ROS), and ultimately induces bacterial death. In the last decade, aSDT has been rapidly developed due to its good penetrative, biocompatibility and targeting properties. This paper highlights the recent aSDT advances in antimicrobial applications. We review aSDT mechanisms and sonosensitizers types, and propose relevant strategies to improve aSDT effects in terms of improving hypoxia and combining applications with other therapies. Furthermore, we summarize the potential obstacles and opportunities for the advancement of aSDT, and provide a deeper understanding of sonodynamic therapy (SDT) for antimicrobial applications, thereby promoting further innovation and clinical application.

Periodontal and oral mucosal diseases are prevalent oral health challenges. Thanks to the natural constraints imposed by the moist and complex intraoral environment, current therapeutic modalities are significantly limited by two key issues: inefficient, low sustained drug release and short intraoral drug retention times, both of which compromise therapeutic efficacy. To address these challenges, hydrogels—a novel class of biomaterials with unique biological and physicochemical properties—have emerged as promising solutions. Hydrogels, with their 3-dimensional (3D) polymer network, are promising biological reagents, particularly for drug delivery. They achieve controlled and sustained release at target sites, and coupled to their therapeutic outcomes, their use in oral healthcare is critical. Consequently, hydrogels have been extensively investigated in both foundational and clinical research, particularly within a wound dressing context. This article systematically examines the limitations associated with conventional therapies and elucidates the mechanisms underpinning the therapeutic efficacy of hydrogels in managing different periodontal and oral mucosal diseases. Furthermore, we explore the clinical challenges and opportunities associated with applying hydrogel-based strategies in oral therapeutics, and we propose future directions for hydrogel research and development.