Electrospun biomaterials and structures for the regeneration of tendons and ligaments: development and biomechanical validation

Tendons and ligaments injuries are nowadays an unsolved clinical problem. The main criticality of the regeneration or replacement of the tendon and ligament tissue, resides in the difficulty of being able to restore the complex hierarchical structure of collagen fibrils that compose them while maintaining their mechanical properties. Tissue engineering has attempted to answer to these problems producing constructs, called scaffolds, able to guide the cells growth. Among the different technologies developed for the production of scaffolds for soft tissues, the electrospinning technique is the most promising. Thanks to its ability to produce fibers with the same diameter of the collagen fibrils in the human body, it has been proved to guide cells proliferation and regeneration of different tissues. In the present Thesis, thanks to this technology, hierarchically nanofibrous structures were developed. Such structures have shown to be morphologically and mechanically able to simulate the hierarchical structure and the biomechanical properties of whole tendons and ligaments. The alignment and proliferation of cells along the nanofibers direction was confirmed in vitro. Furthermore, a complete morphological characterization of the nanofibrous scaffolds was also carried out by using a high-resolution x-ray tomographic investigation. In conclusion, this Thesis proposes promising devices and innovative production techniques, able to be a turning point in the production of electrospun scaffolds and devices for the regeneration, the replacement and the simulation of tendons and ligaments.