Cranial injuries resulting from explosions or gunshot wounds often present with intricate bone and soft tissue defects, demanding elaborate reconstruction methodologies. Current practices involve using autologous and alloplastic materials, tailored according to the specific requirements of the defect in question. However, challenges arise when adapting universal alloplastic materials, leading to structural irregularities and potential implant failure due to geometric and structural and thus aesthetic inadequacies. Moreover, the typical production time for a high cost tailored alloplastic implant is several weeks. Pure autologous reconstruction is frequently infeasible owing to limited availability and the potential for autolysis with the body's immune system dissolving the reimplanted bone tissue. Given these challenges, this study investigates the utilization of additive manufacturing, specifically 3D printing, to produce novel, low-cost and rapidly available patient-specific implants. Our method aims at merging the precision of autologous bone replacements with the accessibility of alloplastic substitutes by crafting the latter intraoperatively based on patient-specific CT scans. A series of three non-traumatic cases is presented, in which for medical reasons the necessity arose to cover a surgically produced skull defect within the same surgical session; in these cases, we used tailored, 3D printed craniotomy templates and the corresponding cranioplasty molds which were produced based on the patients CT scan, to intraoperatively produce patient-specific cranioplasties from PMMA, a widely available low-cost material. The surgical results were highly satisfactory in all three cases. The ultimate objective is to adapt this efficient creation of tailored low cost PMMA implants for complex skull defect reconstruction also for the use in traumatic head injuries. The technique has a high potential for use within the framework of military medicine, given that it can be adapted for use in field hospitals (role 2e and role 3) by just adding a 3D printing device to its equipment. Given the low cost, the wide availability of the materials and the velocity of the process, it may speed up the definitive management of skull defects even in situations with high numbers of combat related head injuries.