Optimized fitting of a midface implant to anchor a magnetic nasal prosthesis using 3D printing

Background Plate-based anchorage systems for craniofacial prostheses offer advantages over extraoral solitary titanium implants in terms of the flexible choice of mounting points and higher stability. Disadvantages become apparent in the complex individual intraoperative adaptation of the plate-based systems to the usually poorly accessible bone. The current article presents a method to overcome these disadvantages and make greater use of the advantages of plate-based systems. Materials and methods The bony midface of a patient who had undergone rhinectomy for cancer of the nasal entrance was reconstructed as a virtual 3D model based on preoperative CT. The open-source software (3D-Slicer) allowed easy and fast reconstruction as well as adaptation for 3D printing using transparent plastic (MED610; stratasys Ltd., MN, USA). Results A titanium mini-plate (MEDICON) for anchoring the nasal prosthesis could be fitted extremely precisely on the midface 3D print. Important anatomical structures were spared, and screw placement was selected according to the individual bone thickness. Implantation of the in-advance fitted titanium plate was performed without complications and without further adjustments. Conclusion In-advance fitting of plate-based systems for anchorage of craniofacial prostheses using 3D printing of the midface overcomes their disadvantages of time-consuming and possibly imprecise individual adaptation. This method further exploits the advantages of higher stability through more possible mounting points, even in thinner bone, to prevent loosening. In addition, in-advance fitting of titanium plates on the 3D model enables better identification and protection of important anatomical structures and shortens operative time.