Bone regeneration with a combination of nanocrystalline hydroxyapatite silica gel, platelet-rich growth factor, and mesenchymal stem cells: a histologic study in rabbit calvaria (original) (raw)

2013, Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology

Objective. This study aimed to assess NanoBone as a carrier construct for mesenchymal stem cells (MSCs) and platelet-rich growth factor (PRGF). Study Design. In the calvarial bone of 8 mature New Zealand White male rabbits, four 8-mm defects were created. Each defect received one of the following treatments: Group 1, 0.2 mg Nano-hydroxyapatite (HA) granule ϩ 2 mL culture medium; Group 2, 0.2 mg Nano-HA ϩ 1 mL autologous PRGF ϩ 2 mL acellular culture medium; Group 3, 0.2 mg Nano-HA ϩ 2 mL culture medium containing 100,000 autogenous MSCs; Group 4, 0.2 mg Nano-HA ϩ 2 mL culture medium containing 100,000 autogenous MSCs ϩ 1 mL autologous PRGF. Result. Histomorphometric analysis at 6 and 12 weeks demonstrated significantly higher bone formation in group 4 (29.45% and 44.55%, respectively) (P Ͻ .05). Bone formation in groups 1, 2, and 3 were as follows: 11.35% and 32.53%, 29.10% and 39.74%, and 25.82% and 39.11%, respectively. Conclusions. NanoBone with MSCs and PRGF seems to be an effective combination for bone regeneration in a rabbit calvaria model. (Oral Surg Oral Med Oral Pathol Oral Radiol 2013;115:e7-e15) Nanoscaffolds as the new "state of the art" in the science of delivery systems are carrier constructs made in form of a grid, a scaffold, or a reticulum of nanofibers, and prepared in a multilayer structure. For each layer, fiber characteristics, thickness, and diameter can be separately controlled, which in turn allows for the manipulation of the porosity, surface area, and thickness of the nanoscaffold. 1-3 NanoBone (Artoss, Rostock, Germany) is a granular composite of synthetic nanocrystalline hydroxyapatite (HA) and silica gel matrix, consisting of interconnected pores sized 10 to 20 nm. 1 The large surface area of NanoBone (84 m 2 /g) is attributable to its high porosity (60%), which provides a scaffold with high osteoconductive and angiogenic properties. 2,4 Favorable biocompatibility and biodegradability of the product, make NanoBone a potential replacement for autografts in the future of bone-augmentation procedures. The controlled absorbency and high porous structure of nanoscaffolds might also affect the proper adherence of mesenchymal stem cells (MSCs) to the carrier and their further differentiation. 6 Although the proven proliferative and osteogenic differentiation capabilities of multipotential MSCs 7-9 has rendered them major associates in bone-regeneration operations, 10,11 MSC delivery with synthetic or natural scaffolds has shown a limited amount of bone formation in comparison with autogenous bone graft. 12 To overcome this shortcoming, several studies have mainly focused on the amelioration of cell carriers, 13-15 whereas others have tested the inductivity of various growth and differentiating factors on MSC-based osteogenesis.