Translational Research: Palatal-derived Ecto-mesenchymal Stem Cells from Human Palate: A New Hope for Alveolar Bone and Cranio-Facial Bone Reconstruction

Abstract

The management of facial defects has rapidly changed in the last decade. Functional and esthetic requirements have steadily increased along with the refinements of surgery. In the case of advanced atrophy or jaw defects, extensive horizontal and vertical bone augmentation is often unavoidable to enable patients to be fitted with implants. Loss of vertical alveolar bone height is the most common cause for a non primary stability of dental implants in adults. At present, there is no ideal therapeutic approach to cure loss of vertical alveolar bone height and achieve optimal pre-implantological bone regeneration before dental implant placement. Recently, it has been found that specific populations of stem cells and/or progenitor cells could be isolated from different dental resources, namely the dental follicle, the dental pulp and the periodontal ligament. Our research group has cultured palatal-derived stem cells (paldSCs) as dentospheres and further differentiated into various cells of the neuronal and osteogenic lineage, thereby demonstrating their stem cell state. In this publication will be shown whether paldSCs could be differentiated into the osteogenic lineage and, if so, whether these cells are able to regenerate alveolar bone tissue in vivo in an athymic rat model. Furthermore, using these data we have started a proof of principle clinical- and histological controlled study using stem cell-rich palatal tissues for improving the vertical alveolar bone augmentation in critical size defects. The initial results of the study demonstrate the feasibility of using stem cell-mediated tissue engineering to treat alveolar bone defects in humans.

Keywords: Athymic immunodeficient rats; Human palatal-derived stem cells (paldSCs); Osteogenic differentiation; Osteoplastic surgical methods; Proof of principle clinical-and histologically-con; Stem-cell enriched palatal-derived tissues.

Fig. 1.

SEM: Cultured palatal-derived stem cells (paldSC) form spheres.

Fig. 2.

Experimental setting on an athymic rat model.

Fig. 3.

Allogen human bone rings (maxgraft^® bonering, botiss bio-materials, Germany) with preserved biomechanical properties: Sterile without antigenic effects, Storable at room temperature for 5 years, Osteoconductive properties supporting natural and controlled tissue remodeling.

Fig. 4.

X-ray situation after loading and finally clinical result with placed implants and superconstruction.