In vivo evaluation of additively manufacturedmulti-layered scaffold for the repair of large osteochondral defects

The repair of osteochondral defects is one of the major clinical challenges in orthopaedics.Well-established osteochondral tissue engineering methods have shown promising results for the early treatment of small defects.However,less success has been achieved for the regeneration of large defects,which is mainly due to the mechanical environment of the joint and the heterogeneous nature of the tissue.In this study,we developed a multi-layered osteochondral scaffold to match the heterogeneous nature of osteochondral tissue by harnessing additive manufacturing technologies and combining the established art laser sintering and material extrusion techniques.The developed scaffold is based on a titanium and polylactic acid matrix-reinforced collagen“sandwich”composite system.The microstructure and mechanical properties of the scaffold were examined,and its safety and efficacy in the repair of large osteochondral defects were tested in an ovine condyle model.The 12-week in vivo evaluation period revealed extensive and significantly higher bone in-growth in the multi-layered scaffold compared with the collagen–HAp scaffold,and the achieved stable mechanical fixation provided strong support to the healing of the overlying cartilage,as demonstrated by hyaline-like cartilage formation.The histological examination showed that the regenerated cartilage in the multi-layer scaffold group was superior to that formed in the control group.Chondrogenic genes such as aggrecan and collagen-II were upregulated in the scaffold and were higher than those in the control group.The findings showed the safety and efficacy of the cell-free“translation-ready”osteochondral scaffold,which has the potential to be used in a one-step surgical procedure for the treatment of large osteochondral defects.

Biomaterials and additive manufacturing:osteochondral scaffold innovation applied to osteoarthritis(BAMOS project)

Osteoarthritis(OA)is a degenerative joint disease,typified by a loss of quality of cartilage and changes in bone at the interface of a joint,resulting in pain,stiffness,and reduced mobility."According to the World Health Organization,40%of people over the age of 70 have OA.This joint disease

Translation through collaboration:practice applied in BAMOS project in in vivo testing of innovative osteochondral scaffolds

Osteoarthritis is the most common chronic degenerative joint disease,recognized by the World Health Organization as a public health problem that affects millions of people worldwide.The project Biomaterials and Additive Manufacturing:Osteochondral Scaffold(BAMOS)innovation applied to osteoarthritis,funded under the frame of the Horizon 2020 Research and Innovation Staff Exchanges(RISE)program,aims to delay or avoid the use of joint replacements by developing novel cost-effective osteochondral scaffold technology for early intervention of osteoarthritis.The multidisciplinary consortium of BAMOS,formed by international leading research centres,collaborates through research and innovation staff exchanges.The project covers all the stages of the development before the clinical trials:design of scaffolds,biomaterials development,processability under additive manufacturing,in vitro test,and in vivo test.This paper reports the translational practice adopted in the project in in vivo assessment of the osteochondral scaffolds developed.

Predictability of Plastic Parts Behaviour Made from Rapid Manufacturing

One of the most important issues to resolve in parts manufactured from rapid manufacturing (RM) technologies is to know their behavior working under real conditions. Total quality manufacturing (TQM) is only possible if mechanical properties are well known in the design stage depending on the processing parameters. This work is mainly focused on testing of several samples made with different selective laser sintering (SLS) parameters and technologies. This procedure is the starting point to establish a basis for designing for RM and the standardization of RM testing. The experiments and the analysis of variance (ANOVA) analyzed the effects of several factors on mechanical properties. The SLS technologies were 3DSystem and EOS. The results show which factor has a large effect on the variables and the interaction between them. The conclusions are very useful for developing rules for designing (designing for RM) and creating new standard rules (ISO, AISI, and DIN) for RM materials and parts testing. The ANOVA gives a better knowledge of the effects of these factors and eliminates unimportant parameters.