Scaffolds for connective tissue regeneration

In most skeletal tissue applications, an ideal scaffolds should be biocompatible and biodegradable in medium-long term; it should initially maintain its structural behaviours, allow cellular ingrowth and diffusion of nutrient, and used as carrier of growth factors and drugs. Actually many synthetic, natural and semi-synthetic organic and inorganic materials have been used, and even if they posses appropriate biological and biodegradable properties, their structural performances are not completely adequate. In order to satisfy all the complex requirement, composites polymer based materials technology can be implemented to designed an appropriate scaffolds. This technology will permits to design bio-inspired structure following the learning from nature approach that is applied to design scaffolds for bone, meniscus and intervertebral disc (nucleus) regeneration. For bone tissue reconstruction, in order to modulate mechanical properties and cell interaction, composite scaffolds made of poly(å-caprolactone) and hydroxyapatite were obtained by phase inversion and salt leaching technique. Both techniques permits to obtain scaffold with controlled micro and macro porosity. Poly(å-caprolactone) based polymers reinforced with degradable fibres were processed by composite technology, phase inversion and salt leaching technique to obtain scaffolds for meniscus regeneration. Injectable gel-like scaffolds were prepared by using esters of hyaluronic acid are used to engineer an nucleus pulposus substitute able to reproduce the viscoelastic properties of NP as well as to guide and promote bone marrow stem cells to adhere and differentiate according to a tissue engineering approach. The composite technology permits to design scaffolds with multifunctional behaviours: biodegradability, mechanical behaviour, cell viability, transport activity, to enhance the neo-tissue formation, determining the functionality and efficacy of the tissue engineered construct.