Current advances in solid free-form techniques for osteochondral tissue engineering

Osteochondral (OC) lesions are characterized by defects in two different zones, the cartilage region and subchondral bone region. These lesions are frequently associated with mechanical instability, as well as osteoarthritic degenerative changes in the knee. The lack of spontaneous healing and the drawbacks of the current treatments has increased the attention from the scientific community to this issue. Different tissue engineering approaches have been attempted using different polymers and different scaffolds' processing. However, the current conventional techniques do not allow the full control over scaffold fabrication, and in this type of approaches, the tuning ability is the key to success in tissue regeneration. In this sense, the researchers have placed their efforts in the development of solid free-form (SFF) techniques. These techniques allow tuning different properties at the micro-macro scale, creating scaffolds with appropriate features for OC tissue engineering. In this review, it is discussed the current SFF techniques used in OC tissue engineering and presented their promising results and current challenges.The authors would like to thank H2020-MSCA-RISE program, as this work is part of developments carried out in BAMOS project, funded from the European Union's Horizon 2020 research and innovation program under grant agreement Nº 734156. The Portuguese Foundation for Science and Technology (FCT) distinctions attributed to J. Silva-Correia (IF/00115/2015) and J. Miguel Oliveira (IF/01285/2015) under the Investigator FCT program are greatly acknowledged. FCT/MCTES is also acknowledged for the PhD scholarship attributed to J. B. Costa (PD/BD/113803/2015).info:eu-repo/semantics/publishedVersio