Additive manufacturing (AM) or three-dimensional (3D) printing has introduced a novel production method in design, manufacturing, and distribution to end-users. This technology has provided great freedom in design for creating complex components, highly customizable products, and efficient waste minimization. The last industrial revolution, namely industry 4.0, employs the integration of smart manufacturing systems and developed information technologies. Accordingly, AM plays a principal role in industry 4.0 thanks to numerous benefits, such as time and material saving, rapid prototyping, high efficiency, and decentralized production methods. This review paper is to organize a comprehensive study on AM technology and present the latest achievements and industrial applications. Besides that, this paper investigates the sustainability dimensions of the AM process and the added values in economic, social, and environment sections. Finally, the paper concludes by pointing out the future trend of AM in technology, applications, and materials aspects that have the potential to come up with new ideas for the future of AM explorations.

Additive manufacturing (AM) is recently imposing as a fast, reliable, and highly flexible solution to process various materials, that range from metals to polymers, to achieve a broad variety of customized end-goods without involving the injection molding process. The employment of biomaterials is of utmost relevance as the environmental footprint of the process and, consequently, of the end-goods is significantly decreased. Additive manufacturing can provide, in particular, an all-in-one platform to fabricate complex-shaped biobased items such as bone implants or biomedical devices, that would be, otherwise, extremely troublesome and costly to achieve. Polyhydroxyalkanoates (PHAs) is an emerging class of biobased and biodegradable polymeric materials achievable by fermentation from bacteria. There are some promising scientific and technical reports on the manufacturing of several commodities in PHAs by additive manufacturing. However, many challenges must still be faced in order to expand further the use of PHAs. In this framework, the present work reviews and classifies the relevant papers focused on the design and development of PHAs for different 3D printing techniques and overviews the most recent applications of this approach.