Trabecular Titanium™ (TT) is a novel material with a structure similar to trabecular bone, already used for prosthetic clinical applications. Being the bone-implant interface the weakest point during the initial healing period, the association of TT with a hydrogel enriched with progenitor cells and osteoinductive factors may represent a promising strategy to improve prosthesis osteointegration. In a previous in vitro study we evaluated the ability of an ammidated carboxymethylcellulose hydrogel (CMCA) and of TT enriched with CMCA to support bone marrow mesenchymal stem cells (BMSCs) viability and osteogenic differentiation [1]. The aim of this study was to evaluate in vivo if the association of TT with CMCA enriched with strontium chloride (SrCl2) and BMSCs could ameliorate TT osteointegration. This study combines TT with CMCA, SrCl2 and BMSCs. To mimic prosthesis-bone implants, TT discs were seeded with human BMSCs predifferentiated in osteogenic medium, then press-fit into engineered bone. A total of 36 athymic mice were implanted subcutaneously, each animal received 2 constructs as un-seeded TT and TT+CMCA or cell seeded TT+BMSCs and TT+CMCA+BMSCs. After 4, 8 and 12 weeks, osteodeposition, bone mineral density (BMD) and osteointegration were evaluated by fluorescence imaging, micro-CT, SEM, histology and pull-out tests.INTRODUCTION
METHODS
