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Biomaterials rapid prototyping (RP), recently known as additive manufacturing (AM), has appeared as a revolutionary technology, promising to transform research into medical therapeutics. RP is a layer by layer manufacturing process which directly translates computer data such as Computer Aided Design (CAD), Computer Tomography (CT), and Magnetic Resonance Imaging (MRI) into three‐dimensional (3D) objects. RP technologies play a significant role in biomedical industry such as anatomical models for surgery training/planning, rehabilitation, dentistry, customized implants, drug delivery devices, tissue engineering, and organ printing. The integration of biomaterials and rapid prototyping technologies is an exciting route in developing biomaterial implants for the past decade. This review describes and classifies the RP systems into three categories of liquid‐based, solid‐based, and powder‐based according to the initial form of their feed materials. Then, discusses possible benefits, drawbacks, and applications of each process in the field of biomaterials science and engineering.

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Hypoxia, the result of disrupted vasculature, can be categorized in the main limiting factors for fracture healing. A lack of oxygen can cause cell apoptosis, tissue necrosis, and late tissue healing. Remedying hypoxia by supplying additional oxygen will majorly accelerate bone healing. In this study, biphasic calcium phosphate (BCP) scaffolds were fabricated by robocasting, an additive manufacturing technique. Then, calcium peroxide (CPO) particles, as an oxygen-releasing agent, were coated on the BCP scaffolds. Segmental radial defects with the size of 15 mm were created in rabbits. Uncoated and CPO-coated BCP scaffolds were implanted in the defects. The empty (control) group received no implantation. Repairing of the bone was investigated via X-ray, histological analysis, and biomechanical tests at 3 and 6 months postoperatively, with immunohistochemical examinations at 6 months after operation. According to the radiological observations, formation of new bone was augmented at the interface between the implant and host bone and internal pores of CPO-coated BCP scaffolds compared to uncoated scaffolds. Histomorphometry analysis represented that the amount of newly formed bone in the CPO-coated scaffold was nearly two times higher than the uncoated one. Immunofluorescence staining revealed that osteogenic markers, osteonectin and octeocalcin, were overexpressed in the defects treated with the coated scaffolds at 6 months of postsurgery, demonstrating higher osteogenic differentiation and bone mineralization compared to the uncoated scaffold group. Furthermore, the coated scaffolds had superior biomechanical properties as in the case of 3 months after surgery, the maximal flexural force of the coated scaffolds reached to 134 N, while it was 92 N for uncoated scaffolds. The results could assure a boosted ability of bone repair for CPO-coated BCP scaffolds implanted in the segmental defect of rabbit radius because of oxygen-releasing coating, and this system of oxygen-generating coating/scaffold might be a potential for accelerated repairing of bone defects.

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