Patients with skull defects after craniotomy for example tumor resection, head trauma, stroke, need a reimplantation of the bone afterwards. For some circumstances, their own bone cannot be reimplanted due to infection, tumor infiltration, damage to the bone, or aseptic bone necrosis. In these cases a Patient Specific Implant (PSI) needs to be designed to fit into the patient`s skull defect. Several materials are currently used such as titanium, poly-ether-ether-ketone (PEEK) or poly-methylmethyl-acrylate (PMMA) for PSI fabrication. At the moment, PSI are commercially available from different companies (DePuy Synthes®, EOS®, Xilloc®). Apart from the high costs of commercially available PSI, it takes usually several weeks until the designed and manufactured PSI is delivered to the hospital ready for reimplantation.