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In 3D printing technique, a preprogrammed printer head moves over the target surface and ejects a fixed quantity of molten polymer on the target in order to create the final desired shape. For attaining the final 3D structure, the movable printer head deposits the polymer material in a layer‐by‐layer fashion. This process is also known as Rapid Prototyping and has prominent applications in biomedical fields such as dental implants [40], orthopedic prosthetics [41, 42], 3D surgical and medical models, and also hearing aids. 3D bioprinting, a new technique, is nothing but a variation of traditional 3D printing in which 3D biofunctional structures are engineered. It involves the deposition of living cells onto a gel medium [43]. Some studies have used nanomaterials in conjunction with biohybrid scaffolds to create additional functions [44]. Some examples show that, new bone growth could be induced by adding magnesia nanoparticles to PCL–chitosan nanofibers through modulation of signal transduction and cell proliferation [44]. In another example, it has been found that this cell proliferation could also be induced by means of magnetic heating when magnetic nanoparticles are added to PCL–chitosan nanofibers [45].

In the field of tissue engineering, electrospinning and 3D printing are the most common techniques by which the scaffolds are fabricated. In addition to these techniques, common biomedical supplies are prepared by conventional techniques such as compression molding or injection molding. In recent years, in order to combine the advantages of both, a combination of advanced methods and conventional techniques is used to reduce the overall processing time and cost. Examples include particulate leaching and solvent casting [46].