Optimised Vascular Network for Skin Tissue Engineering by Additive Manufacturing

Artificial vascular vessels, including arteries, veins and capillaries, are being printed using additive manufacturing technologies. Additive manufacturing allows the manufacture of artificial blood vessels and their networks of any sophisticated geometry. This chapter demonstrates the essential and efficient methods to design and fabricate optimal vascular network for tissue engineering structures following the physiological conditions. Comprehensive physiological requirements in both micro- and macro-scales were considered in developing the optimisation design for artificial vascular networks. The optimised vascular vessel offers three advantages: (1) it provides the maximum nutrient supply; (2) it minimises the recirculation areas and (3) it allows the wall shear stress on the vessel in a healthy range. Two main design technologies are used in the chapter to achieve the design. They are computer graphics and computational fluid dynamics. The optimised design was then manufactured by the stereolithography process using materials that are biocompatible, elastic and surface bio-coatable. The stereolithography manufactured vascular vessels were embedded in the hydrogel seeded with cells afterward. The results of in vitro studies show that the optimised vascular network has the lowest cell death rate compared with a pure hydrogel scaffold and a hydrogel scaffold embedded within a single tube in day seven. The combination of the optimised micro- and macro-design, the material selection and the manufacturing methods completes a general guide for future artificial vascular vessel network developments.