Mesenchymal stem cells are highly regarded for their potential in tissue repair and regenerative medicine due to their multipotency and self-renewal abilities. Recently, mesenchymal stem cells have been redefined as "medical signaling cells," with their primary biological effects mediated through exosome secretion. These exosomes, which contain lipids, proteins, RNA, and metabolites, are crucial in regulating various biological processes and enhancing regenerative therapies. Exosomes replicate the effects of their parent cells while offering benefits such as reduced side effects, low immunogenicity, excellent biocompatibility, and high drug-loading capacity. Dental stem cells, including those from apical papilla, gingiva, dental pulp, and other sources, are key contributors to exosome-mediated regenerative effects, such as tumor cell apoptosis, neuroprotection, angiogenesis, osteogenesis, and immune modulation. Despite their promise, clinical application of exosomes is limited by challenges in isolation techniques. Current methods face issues of complexity, inefficiency, and insufficient purity, hindering detailed analysis. Recent advancements, such as micro-electromechanical systems, alternating current electroosmosis, and serum-free three-dimensional cell cultures, have improved exosome isolation efficacy. This review synthesizes nearly 200 studies on dental stem cell-derived exosomes, highlighting their potential in treating a wide range of conditions, including periodontal diseases, cancer, neurodegenerative disorders, diabetes, and more. Optimized isolation methods offer a path forward for overcoming current limitations and advancing the clinical use of exosome-based therapies.
Exosomes/physiology* ; Humans ; Mesenchymal Stem Cells/cytology* ; Dental Pulp/cytology* ; Stem Cells/cytology* ; Tooth/cytology*

Platelet-rich fibrin (PRF) has been widely used owing to its ability to stimulate tissue regeneration. To date, few studies have described the antibacterial properties of PRF. Previously, PRF prepared by horizontal centrifugation (H-PRF) was shown to contain more immune cells than leukocyte- and platelet-rich fibrin (L-PRF). This study aimed to compare the antimicrobial effects of PRFs against Staphylococcus aureus and Escherichia coli in vitro and to determine whether the antibacterial effects correlated with the number of immune cells. Blood samples were obtained from eight healthy donors to prepare L-PRF and H-PRF. The sizes and weights of L-PRF and H-PRF were first evaluated, and their antibacterial effects against S. aureus and E. coli were then tested in vitro using the inhibition ring and plate-counting test methods. Flow-cytometric analysis of the cell components of L-PRF and H-PRF was also performed. No significant differences in size or weight were observed between the L-PRF and H-PRF groups. The H-PRF group contained more leukocytes than the L-PRF group. While both PRFs had notable antimicrobial activity against S. aureus and E. coli, H-PRF demonstrated a significantly better antibacterial effect than L-PRF. Furthermore, the antimicrobial ability of the PRF solid was less efficient than that of wet PRF. In conclusion, H-PRF exhibited better antibacterial activity than L-PRF, which might have been attributed to having more immune cells.
Anti-Bacterial Agents/pharmacology* ; Anti-Infective Agents ; Centrifugation ; Escherichia coli ; Leukocytes ; Platelet-Rich Fibrin ; Staphylococcus aureus