Polyurethane-based structures obtained by additive manufacturing technologies

Abstract

Three dimensional (3D) printing, also known as rapid prototyping or additive manufacturing, is a layer by layer process to create objects from 3D computer-aided design (CAD) data. This is a very suitable technology for personalized biomedical applications, due its inherent advantages of customizability and the ability to create complex shapes with precision. Moreover, this is a time-saving approach, being far more reproducible than conventional techniques to obtain scaffolds. Nowadays, there are many forms of 3D printing commercially available besides stereolithography (SLA), including selective laser sintering (SLS), laminated object modeling (LOM), and fused deposition modeling (FDM). 3D printing is being used in the fields of otorhinolaryngology, dentistry, orthopedics, and craniofacial reconstruction, among others. However, there are some limitations to the material properties for processing through every technique. Furthermore, there is an increasing need of new biocompatible and/or bioresorbable materials with different mechanical properties, degradation rate, and surface requirements to be processed for a broader range of applications. Polyurethanes and their composites with poly(ethylene glycol), cellulose, starch, gelatin, alginate, fibrinogen, and collagen, among others, have been explored through different 3D printing techniques for biomedical applications in the last years. In this work, advantages and disadvantages of the current approaches, as well as future perspectives are outlined.