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Additive manufacturing (AM), commonly known as 3D printing, can be defined as the "process of joining materials to make parts from 3D model data, usually layer upon layer, as opposed to subtractive manufacturing and formative manufacturing methodologies" in the International Organization for Standardization (ISO)/American Society for Testing and Materials (ASTM) 52900:2015 standard. Based on the standard, AM processes can be classified into the following categories: (1) material extrusion; (2) directed energy deposition; (3) solidification of powder; (4) photopolymerization and (5) sheet lamination.

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Dr. Gehan T. El-Bassyouni, Professor of Biomaterials, National Research Centre (NRC) Egypt since 31/05/2010. I´ve been a researcher for two years at Johns Hopkins University, School of Medicine, Maryland USA and at Pennsylvania University, USA. I also have a 10 years teaching experience. I have more than 50 international publications.

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