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The purpose of this paper is to describe the fabrication and characterization of poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyexanoate] (PHBHHx) tissue engineering scaffolds with anatomical shape and customized porous structure.

Scaffolds with external shape and size modeled on a critical size segment of a rabbit’s radius model and an internal macrochanneled porous structure were designed and fabricated by means of a computer-aided wet-spinning (CAWS) technique. Morphological, thermal and mechanical characterization were carried out to assess the effect of the fabrication process on material properties and the potential of the PHBHHx scaffolds in comparison with anatomical star poly(e-caprolactone) (*PCL) scaffolds previously validated in vivo.

The CAWS technique is well suited for the layered manufacturing of anatomical PHBHHx scaffolds with a tailored porous architecture characterized by a longitudinal macrochannel. Morphological analysis showed that the scaffolds were composed by overlapping layers of microfibers with a spongy morphology, forming a 3D interconnected network of pores. Physical-chemical characterization indicated that the used technique did not affect the molecular structure of the processed polymer. Analysis of the compressive and tensile mechanical properties of the scaffolds highlighted the anisotropic behavior of the porous structure and the effect of the macrochannel in enhancing scaffold compressive stiffness. In comparison to the *PCL scaffolds, PHBHHx scaffolds showed higher compressive stiffness and tensile deformability.

This study shows the possibility of using renewable microbial polyester for the fabrication of scaffolds with anatomical shape and internal architecture tailored for in vivo bone regeneration studies.

Additive manufacturing (AM) or solid freeform fabrication (SFF) technique is extensively used to produce intrinsic 3D structures with high accuracy. Its significant contributions in the field of tissue engineering (TE) have significantly increased in the recent years. TE is used to regenerate or repair impaired tissues which are caused by trauma, disease and injury in human body. There are a number of novel materials such as polymers, ceramics and composites, which possess immense potential for production of scaffolds. However, the major challenge is in developing those bioactive and patient-specific scaffolds, which have a required controlled design like pore architecture with good interconnectivity, optimized porosity and microstructure. Such design not only supports cell proliferation but also promotes good adhesion and differentiation. However, the traditional techniques fail to fulfill all the required specific properties in tissue scaffold. The purpose of this study is to report the review on AM techniques for the fabrication of TE scaffolds.

The present review paper provides a detailed analysis of the widely used AM techniques to construct tissue scaffolds using stereolithography (SLA), selective laser sintering (SLS), fused deposition modeling (FDM), binder jetting (BJ) and advanced or hybrid additive manufacturing methods.

Subsequently, this study also focuses on understanding the concepts of TE scaffolds and their characteristics, working principle of scaffolds fabrication process. Besides this, mechanical properties, characteristics of microstructure, in vitro and in vivo analysis of the fabricated scaffolds have also been discussed in detail.

The review paper highlights the way forward in the area of additive manufacturing applications in TE field by following a systematic review methodology.

The purpose of this research is to design 3D print and analyze mechanical as well as microstructural behavior of interlaced fibrous structures using Dremel 3D45 additive manufacturing (AM) machine.

A series of plain and twill weave fabrics are designed using computer-aided design software Solidworks and printed using fused deposition modeling machines to determine the best model that could be printable. The structures were designed in such a way that the fabricated yarns with pure (PLA) were not sticking to each other in the fabric structure. The specimens were printed in vertical orientation and then tensile and three-point bending (flexural) tests were conducted for twill weave fabrics.

The tests showed that the mechanical strength was higher in the warp direction than in the weft direction. This difference was because of printing of continuous filament-like yarns in the warp direction and staple-like yarns in the weft direction. This orthotropic property of the material was verified by analyzing its microscopic structures via optical microscope.

Future work should include improvement of the structure and exploration of different polymers and their composites to increase the tensile, bending and other strengths to make the 3D-printed structures more flexible and stronger. Future research should also focus on the large-scale manufacturing of 3D printed fabrics.

This paper supports work on wearable 3D-printed fabrics. The 3D-printed fabric will also contribute to new applications and products such as liquid filters.

The research done in this work is new and original. This paper contributes to new knowledge by providing a better understanding of polymers and their 3D printing capabilities to form a complex fabric structure.

Electrospinning is a method of the polymer super thin fibres formation by the electrostatic field. The distribution of electrostatic field affects the effectiveness of the electrospinning.

This paper presents various computer models that can improve the electrospinning process. The possibilities of modelling the electrostatic field in the design of electrospinning equipment are presented.

In the research part, the one focussed on finding a cylinder-shaped collector structure to limit the adverse effect of an uneven distribution of the electric field intensity on the collector.

The paper concerns the improvement of the electrospinning process with the use of electrostatic field modelling. In the first part, several possible applications of electrostatic models have been indicated, thanks to which the efficiency of the process has been improved. The original solution of the collector geometry was presented, which according to the authors, in comparison with previous models, gives the most promising results. In this solution, it was possible to obtain an even distribution of the electric field intensity while removing the unfavourable effect of the field strength increase on the outer edges of the collector. The most important aspect in this paper is electric field strength analysis.

Although many researchers have widely studied additive manufacturing (AM) as one of the most important industrial revolutions, few have presented a bibliometric analysis of the published studies in this area. This paper aims to evaluate AM research trends based on 4607 publications most cited from year 2010 to 2020.

The research methodology is bibliometric indicators and network analysis, including analysis based on keywords, citation analysis, productive journal, related published papers and authors indicators. Two free available software were employed VOSviewer and Bibexcel.

Keywords analysis results indicate that among the AM processes, Selective Laser Melting and Fused Deposition Modeling techniques, are the two processes ranked on top of the techniques employed and studied with 35.76% and 20.09% respectively. The citation analysis by VOSviewer software, reveals that the medical applications field and the fabrication of metal parts are the areas that interest researchers greatly. Different new research niches, as pharmaceutical industry, digital construction and food fabrication are growing topics in AM scientific works. This study reveals that journals “Materials & design”, “Advanced materials”, “Acs applied materials & interfaces”, “Additive manufacturing”, “Advanced functional materials” and “Biofabrication” are the most productive and influential in AM scientific research.

The results and conclusions of this work can be used as indicators of trends in AM research and/or as prospects for future studies in this area.