Materiali e Tecnologie per la realizzazione di sostituti ossei per l'ingegneria dei tessuti

Abstract

Scaffolds play a critical role in tissue engineering by acting as a temporary artificial extracellular matrices for cell adhesion, proliferation and differentiated function as well as serving as three dimensional templates for neotissue/organ formation. This thesis have been addressed to the examination of the basic principles and methods oriented to the development of tailored scaffolds for bone tissue regeneration. In this direction, different polycaprolactone based composite scaffolds have been developed through novel and traditional techniques of preparation such as phase inversion/salt leaching, thermal induced phase separation (TIPS) and melting induced microspheres sintering (MIMS)). In order to mimic the mechanical response of the natural bone tissue, different strategies of reinforcement have been adopted by the addition of bioactive fillers (Hydroxyapatite, tricalcium phosphates) or/and biodegradable fibers (polylactide acid). An accurate morphological and functional characterization of proposed scaffolds has been achieved. A qualitative estimation of porosity has been obtained by S.E.M analysis whereas a qualitative analysis of porosity in terms of pore volume fraction, pore size distribution and interconnection degree has been performed by theoretical and experimental methodologies (gravimetric measurements, mercury intrusion porosimetry, two dimensional analysis by dedicated software and three dimensional image analysis by computed micro tomography). Furthermore, a mechanical characterization was also performed to compare their properties with the natural ones.