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Introduction In bioprinting techniques, tissue engineering from 3D models to generate the desired geometry is as important as cell proliferation, as it will be key to the survival of the printed tissue and its functional success. Methods Alginate-based hydrogels were used because they are the most widely used by the scientific community for bioprinting. The alginate-based hydrogels used were characterised using a rheometer to obtain the boundary conditions to be applied in the computational software. A 2D axisymmetric model together with a two-phase flow level set interface of a bioprinting nozzle and a computational model of a human tooth were carried out to verify the results obtained. Results The data showed that droplet detachment occurs at lower pressures based on the higher the percentage of alginate. In addition, samples with a higher percentage of alginate were less sensitive to pressure during extrusion. Conclusions

Introduction In bioprinting, it is essential to correctly characterise the materials to be used in order to ensure the highest cell viability while maintaining the best structural properties of the hydrogels. Methods Alginate-based hydrogels with different concentrations have been characterised because they are currently the ones with the best printing properties according to the literature. The concentrations chosen were 3.5%, 4% and 5% alginate, and then a scaffold was bioprinted with the one with the best mechanical properties. Finally, a 3D model of a tooth was bioprinted to check the integrity of the hydrogel characterised as a somewhat more complex structure than a simple scaffold. Results It could be observed that, despite suffering a similar viscosity loss to the rest, the sample with the best viscosity properties when subjected to shear stresses was the one containing 5% alginate concentration. When a simple scaffold was bioprinted, it was observed that the result was positive, as the visual analysis corresponded to the parameters programmed in 3D design software. Likewise, the subsequent bioprinting of the dental model showed good results. Conclusions The hydrogels characterised by rheometry showed similar behaviour with respect to viscosity. Furthermore, it was found that the hydrogel with higher viscosity allowed for higher quality bioprints.