Abstract
Gel-based delivery systems have emerged as versatile platforms in dentistry due to their biocompatibility, injectability, tunable rheology, and ability to localize therapeutic agents at the site of application. This review synthesizes current evidence on hydrogels, thermosensitive gels, mucoadhesive gels, nanoparticle-loaded gels, and stimuli-responsive systems, highlighting their structural characteristics, mechanisms of drug release, and clinical relevance. Mucoadhesive formulations demonstrate prolonged retention in periodontal pockets and oral mucosa, improving the efficacy of antimicrobials and anti-inflammatory agents. Thermosensitive gels enable minimally invasive administration and in situ gelation, supporting controlled release at body temperature. Nanoparticle-loaded gels exhibit enhanced drug stability and deeper tissue penetration, while "smart" gels respond to environmental stimuli such as pH or temperature to modulate release profiles. Clinical findings indicate reductions in probing depth, improved wound healing, decreased bacterial load, and better patient comfort when gel systems are used as adjuncts to mechanical therapy or regenerative procedures. However, despite these advances, challenges such as variability in gel stability, manufacturing reproducibility, regulatory approval pathways, and limited long-term clinical evidence still constrain widespread adoption of these systems in routine practice.