Harnessing Exosomes for Periodontal Regeneration: Biological Rationale, Preclinical Evidence and Barriers to Clinical Translation

Abstract

Periodontitis destroys the tooth-supporting apparatus through dysregulated interactions among a pathogenic biofilm, host immunity and resident reparative cells. Conventional periodontal therapy can control infection and inflammation, while established regenerative procedures improve selected intrabony and furcation defects, but predictable restoration of cementum, functionally oriented periodontal ligament and alveolar bone remains difficult. Small extracellular vesicles released by mesenchymal stromal and dental stem cells have therefore attracted interest as cell-free mediators capable of coordinating immunomodulation, osteogenesis, angiogenesis and matrix repair. This critical narrative review examines the biological rationale, source-dependent effects, engineering strategies, delivery systems, preclinical efficacy and clinical translation of extracellular-vesicle-based periodontal regeneration. Literature published from 2000 to 21 May 2026 was identified through accessible biomedical and scholarly indexes, trial registries and citation searching, with foundational earlier work included when necessary. The evidence indicates that locally delivered vesicle preparations can reduce inflammatory signalling, alter macrophage phenotypes, protect periodontal ligament cells from oxidative and inflammatory injury, promote osteogenic differentiation and improve radiographic or histomorphometric bone outcomes in rodent defects. Preconditioning, genetic cargo engineering and biomaterial-assisted retention can increase apparent potency, but they also intensify manufacturing and regulatory complexity. Confidence in therapeutic effectiveness remains constrained by inconsistent nomenclature, incomplete separation and characterisation, poorly harmonised dose units, small animal models, frequent reliance on bone-centred surrogate outcomes and limited assessment of cementum-periodontal ligament architecture. Meta-analytic signals favour vesicle therapy, yet extreme heterogeneity and unclear risks of bias prevent reliable effect-size translation. Human evidence is not sufficient to establish regenerative efficacy; an early-phase registered study remains without posted results, while recent clinical investigations have focused on extracellular vesicles as biomarkers rather than therapeutics. Translation will require product definitions aligned with contemporary extracellular-vesicle standards, clinically compatible delivery materials, validated potency assays, rigorous safety and biodistribution studies, and staged randomised trials conducted after effective biofilm control. Small extracellular vesicles are biologically credible adjuncts, but their clinical value depends on replacing proof-of-concept enthusiasm with reproducible product science and functionally meaningful periodontal endpoints.