Bio-Inspired Materials: Exhibited Characteristics and Integration Degree in Bio-Printing Operations

In the last decade, additive manufacturing techniques, commonly known under the term "3d printing" have seen constantly increasing use in various scientific fields. The nature of these fabrication techniques that operate under a layer-by-layer material deposition principle features several de facto advantages, compared to traditional manufacturing techniques. These advantages range from the precise attribution of pre-designed complex shapes to the use of a variety of materials as raw materials in the process. However, its major strong point is the ability to fabricate custom shapes with interconnected lattices, and porous interiors that traditional manufacturing techniques cannot properly attribute. This potential is being largely exploited in the biomedical field in sectors like bio-printing, where such structures are being used for direct implantation into the human body. To meet the strict requirements that such procedures dictate, the fabricated items need to be made out of biomaterials exhibiting properties like biocompatibility, bioresorbability, biodegradability, and appropriate mechanical properties. This review aims not only to list the most important biomaterials used in these techniques but also to bring up their pros and cons in meeting the aforementioned characteristics that are vital in their use.