We have also invited certain notable guests to share their expertise in the field of 3D printing and its future applications.

Tadej Strojnik
Alma Mater Europaea ECM, Slovenia
Patient-specific cranioplasty: evaluation of long-term results

Prof. Dr. Tadej Strojnik is a renowned specialist in neurosurgery with over 25 years of experience in the field. Dr Strojnik has been instrumental in the development of new methods for the treatment of chronic pain and deep brain stimulation and has worked in neurosurgical departments in Slovenia, France and Germany. After many years of dedicated work in the neurosurgery department of the Maribor University Hospital in Slovenia, he moved to Marseille, France, where he worked at the renowned La Timone Clinic, focusing mainly on Gamma Knife therapy. Later, he moved on to Germany, to Rendsburg, where he continued his work in the field of general and spinal neurosurgery. Since 2021, he has established his own private neurosurgical practice and currently works primarily in private clinics. In addition to his clinical work, he is also active in research and teaching. At the medical faculty of the University of Maribor, he holds the post of full professor of surgery, he is also the head of the master's and doctoral program in physiotherapy at the Alma Mater Europaea - European Centre Maribor. During his work at the Maribor University Clinical Centre, he established a fruitful collaboration with the Maribor Faculty of Mechanical Engineering in the area of cranial reconstruction.

Patient-specific cranioplasty: evaluation of long-term results

Tadej Strojnik MD, PhD, 1 Maša Strojnik MD, 2 Toma┼ż Brajlih PhD, 3 Igor Drstvenšek PhD 3 Alma Mater Europaea ECM, 1 University Medical Centre Maribor, 2 Faculty of Mechanical Engineering, University of Maribor 3

Abstract: Skull reconstruction to treat cranial bone defects is an ongoing challenge in the field of neurosurgery. Decompressive craniectomies are now commonly used in treating posttraumatic cerebral oedema and reducing raised intracranial pressure in catastrophic cerebrovascular incidents. In addition, various conditions such as tumor pathology, multi-fragmentary skull fractures, infection, bone re-absorption, and graft rejection result in the need for cranioplasty.

Consequently, surgical bone defects often require correction after the patient undergoes such life-changing events. Although using the patient’s own bone flap is an option, its inadequacies in terms of conservation make it less favourable. Ideally, the material used for cranioplasty should be viable, inert, malleable, available, radiolucent, sterilizable, stable, biocompatible, and inexpensive. Currently available materials for reconstruction include polymethylmethacrylate (PMMA), titanium, ceramics, and other resin and alloy types. However, none of these artificial materials meets all the stated requirements.

Our work aims to demonstrate our experiences and the evolution of our surgical techniques. In the early days, we utilized free-hand modelling of the implant, using the patient's own bone. However, the field has come a long way, and we now create patient-specific custom-made implants by processing CT images using new technologies such as 3D printing and computer-assisted design/manufacturing (CAD/CAM). We will present and discuss illustrative clinical cases to demonstrate the efficacy of our approach, particularly with respect to long-term outcomes.

Key words: cranial defect, scull reconstruction, custom-made implants, 3D printing long term outcome.