Highly porous hybrid scaffolds for bone tissue engineering
Echafaudages hybrides à grande interconnexion de pores destinés à l'ingénierie tissulaire osseuse
Résumé
The concept of Bone Tissue Engineering requires a highly porous scaffold using a suitable
biodegradable material with adequate mechanical and surface properties in order to accelerate cell
recruitment and expression of extracellular matrix. However, numerous existing materials failed to
reconstruct and restore normal physiological structure and function. Currently, hybrid scaffolds
which rely on the combination of existent materials are investigated in order to create a micro-
environment suitable for faster biointegration. Therefore, the aim of our study is the evaluation of a
biodegradable hybrid scaffold (hPEUU) based on a elastomeric poly(ester-uethane-urea) (PEUU)
matrix reinforced by bioceramic particles.
METHODS
The incorporation of the bioceramic particles (OST-Developpement) in PEUU scaffolds was carried
out during the scaffold elaboration by a PolyHIPE technique [1]. Pore size and surface properties
were characterized by SEM. Cross-link density and pore interconnectivity were determined through
swelling measurements. Chemical analyses through different techniques, such as FTIR and EDX,
were performed. Compression assays targeting mechanical behavior were carried out. In vitro
calcification tests in simulated Body fluid were conducted for 7 days [2,3]. In vitro and in vivo
assays were conducted respectively on CSM and in a rat model in order to evaluate the scaffold
biocompatibility and osteoconductive properties.
RESULTS & CONCLUSIONS
Current results showed that the reinforcing-effect of bioceramic particles did not affect the porosity
and the structure of the scaffold. The particles were trapped inside the polymer matrix during the
cross-linking step of the material and the washing steps did not induce a major lost of the mineral
phase. In vitro and in vivo assays results led to conclude osteoconductive properties, bone
regeneration potential and biocompatibility character of hPEUU.