gms | German Medical Science

57th Annual Meeting of the German Society of Neurosurgery
Joint Meeting with the Japanese Neurosurgical Society

German Society of Neurosurgery (DGNC)

11 - 14 May, Essen

Preoperative implant fabrication by fused deposition modeling and virtual simulation of implant fit for cranioplasty

Präoperative Erstellung von Implantaten durch Fused Deposition Modeling und virtueller Simulation der Passgenauigkeit für die Kranioplastie

Meeting Abstract

  • B. Brosdau - Department of Neurosurgery, University Hospital Schleswig-Holstein, Campus Lübeck
  • J. Leppert - Department of Neurosurgery, University Hospital Schleswig-Holstein, Campus Lübeck
  • H. Ssenyonjo - Department of Neurosurgery, University Hospital Schleswig-Holstein, Campus Lübeck
  • S. Gottschalk - Department of Neuroradiology, University Hospital Schleswig-Holstein, Campus Lübeck
  • K. Kramer - Department of Computer-Aided Engineering, University of Applied Sciences, Lübeck
  • J. Wulf - Department of Anatomy, University of Lübeck
  • V. Tronnier - Department of Neurosurgery, University Hospital Schleswig-Holstein, Campus Lübeck
  • corresponding author A. Giese - Department of Neurosurgery, University Hospital Schleswig-Holstein, Campus Lübeck

Deutsche Gesellschaft für Neurochirurgie. Japanische Gesellschaft für Neurochirurgie. 57. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie. Essen, 11.-14.05.2006. Düsseldorf, Köln: German Medical Science; 2006. DocP 02.25

The electronic version of this article is the complete one and can be found online at:

Published: May 8, 2006

© 2006 Brosdau et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Objective: Trauma, calvarian tumors and defects following surgery are the main reasons for large cranial defects. Indications for reconstruction of these defects are cosmetic and protection against mechanical impact. We report a technique of Rapid Prototyping (RP) for custom reconstruction of cranial defects using Fused Deposition Modeling (FDM) and virtual simulation of implant fit and cosmetic result.

Methods: In a cadaver specimen a craniectomy was performed and a model of the defect was built using FDM. Implant design was based on the postoperative imaging data using a mirror image of the contralateral side modified by “free hand” CAD. The CAD data were transformed to a STL format to generate a negative mold by 3D printing using FDM. PMMA implants were formed using the mold and the influence of sterilization techniques on implant form and stability were investigated by optical 3D scanning. The fit of 3D scanned implants into the virtual defect of preoperative CCT reconstructions was studied on colour coded images and compared to preoperative images.

Results: CAD designed 3D printed PMMA implants showed a significantly better fit and cosmetic results than free hand modeled implants. The intraoperative modeling times were more than four times longer than implantation of prefabricated implants and ranged from 26-44 minutes. Sterilization of prefabricated implants by irradiation, gas- and plasma sterilization did not result in changes of the spatial configuration of the implants and had no significant influence on implant stability. Virtual implantation into preoperative CCT 3D reconstructions allowed the visualization of implant fit and the cosmetic result, which was verified by post implantation CCT.

Conclusions: Our results demonstrate that FDM generated anatomical models and negative molds of the defects provide a rapid and highly accurate method of custom implants of skull defect reconstructions. 3D simulation of the implant fit allows preoperative verification of the post operative cosmetic result. Our technique based offers a cost-effective alternative to industrially produced implants.