Mesenchymal stem cells and their challenges for bone regeneration and osseointegration.

Bone regeneration is an indispensable procedure for implant placement. Original techniques based on mesenchymal stromal cell (MSC) therapy are emerging with the goal of speeding up biology, thereby reducing the osseointegration period. Many products found their way in clinical application, yet their reliability remains uncertain because many in vitro culture-related challenges are facing these cells once they are out of their biologic environment. In this commentary, these limitations are discussed with the emphasis of their impact on the performance of MSCs. Clinicians should be aware of these issues before implementing this cell-based regenerative technique.