In the past years, there have been increasing number of reports revealing the potential application of MSCs in the clinical practice 16,17. Cells isolated from dental tissues are a heterogeneous cell population consisting of stem/progenitor cells, fibroblasts, etc.6,18. Isolation of primary stem cell cultures, followed by thorough characterization and investigation of their properties would lead to more predictable results of their in vivo application.

According to some authors, dental MSC have different ability of de novo tissues and structures formation 19. DPSC, SHED and SCAP have the potential to initiate bone, cartilage, and pulpodentin complex regeneration, while PDLSC stimulate formation and regeneration of muscle tissue, tendons, and ligaments 19. The ability of dental MSCs of bone regeneration makes them ideal candidated in the complex management of extensive periodontal bone defects. Their potential to differentiate into bone-like cells and to synthesize a bone matrix has been widely investigated4 8.

Regenerative osteogenic potential of dental MSC can be investigated in vitro after the addition of suitable active molecules in the cell culture media that can induce osteogenic differentiation. Wide number of studies report strong Alizarin red in MSC when cultivated in osteogenic differentiation media 4,8. Other methods, like flow-cytometry markers expression also reveal specific differentiation ability in stem cells 20. The addition of active substances such as vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF) bone morphogenetic protein-bone morphogenetic protein (BMP), etc., in the cell culture media in vitro, affects significantly the differentiation processes21,22,23. BMP family have positive effect on osteogenesis21,23. There is already evidence in the literature of in vivo experiments that demonstrate the ability of BMP to stimulate bone regeneration in peri-implant tissues24. Lee et al.24 report that VEGF stimulates the mineralization of PDL cells, whereas cell cultivation with FGF-2 has an inhibitory effect on the osteogenesis. Each growth factor is having different effects on cells 25. Studies about the effects of growth factors on stem cells would contribute to their introduction in the clinic for the treatment of wide number pathological conditions associated with soft tissue destruction and bone resorption.

Although the functions of dental MSCs are well described in the literature 2,4, reports about their effect in patients in vivo are still scarce. The goal of all MSC studies is their further successful clinical application. Conduction of well-planned experiments, revealing in detaisl the optimal conditions for their proper functioning is needed 19.

MSC with high potential have been isolated from human dental tissues. However, little is known about their regenerative potential in vivo due to the lack of sufficient scientific data about their application in clinical trials. Further research is needed to clarify the effects of various molecules on dental MSC and to reveal the most appropriate conditions of stem cell therapy

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