Comparison of the potential for bioprinting of different 3D printing technologies

Additive manufacturing technologies offer a multitude of medical applications due to the advances in the development of the materials used to reproduce customized model products. The main problem withthesetechnologies is obtaining thecorrect cell viability values, and it is where three-dimensional (3D) bioprinting emerges as a very interesting tool that should be studied extensively, as it has significant disadvantages with respect to printability. In this work, the comparison of 3D bioprinting technology in hydrogels and thermoplastics for the development of biomimetic parts is proposed. To this end, the study of the printability of different materials widely used in the literature is proposed, to subsequently test and analyze the parameters that indicate whether these materials could be used to obtain a biomimetic structure with structural guarantees. In order to analyze the materials studied, different tools have been designed to facilitate the quantitative characterization of their printability using 3D printing. For this purpose, different structures have been developed and a characterization methodology has been followed to quantify the printability value of each material in each test to subsequently discard the materials that do not obtain a minimum value in the result. After the study, it was found that only gelatin methacryloyl (GelMA) 5% could generate biomimetic structures faithful to the designed 3D model. Furthermore, by comparing the printing results of the different materials used in 3D bioprinting and consequently establishing the approach of different strategies, it is shown that hydrogels need to be further developed to match the results achieved by thermoplastic materials used for bioprinting.