Autogenous dentin combined with mesenchymal stromal cells as an alternative alveolar bone graft: an in vivo study

Considering the chemical and structural properties of dentin, this study was aimed at evaluating the effect of dentin matrix alone or combined with mesenchymal stromal cells (MSC) on postextraction alveolar bone regeneration.

Wistar rats were subjected to tooth extraction with osteotomy and allocated into groups according to the graft inserted: (1) Gelita-Spon^®, (2) Bio-Oss^®, (3) Dentin, (4) MSC, (5) Dentin/MSC, and (6) Control. Maxillae were analyzed by means of hematoxylin and eosin (H&E) staining, immunohistochemical (IHC) analysis, microcomputed tomography (micro-CT), and scanning electron microscopy (SEM). Serum levels of calcium and phosphorus were quantified.

The Bio-Oss group showed less bone than Gelita-Spon and Dentin/MSC; no other significant differences were seen in H&E analysis. The Bio-Oss group showed higher expression of collagen type I compared to the Dentin and Dentin/MSC groups and also higher osteocalcin expression than the Dentin/MSC group. There was a tendency of higher expression of osteopontin in the MSC, Dentin, and Dentin/MSC groups and higher VEGF in the MSC group. On micro-CT analysis, the Bio-Oss and the Dentin/MSC groups exhibited greater bone volume than the Control. Serum calcium and phosphorus levels did not significantly differ between the groups. SEM analysis depicted particles of Bio-Oss and dentin in the respective groups, as well as significant cellularity in the MSC group.

Autogenous nondemineralized dentin is an alternative for alveolar bone grafting, which can be improved by combination with MSC.

This work provides support for the clinical applicability of dentin graft alone or combined with MSC.