Malar Symmetrisation Using Patient-Specific Onlay Implant – Case Study 3

CMF Case Study 3 - Malar Symmetrisation Using Patient-Specific Onlay Implant 1

Overview

In this case, 3DLP worked with the surgeon to assist in the design and manufacture of a customised 3D printed titanium plate for a surgical procedure to restore the patient’s malar (cheek) symmetry.

Segmentation

3DLP received the CT scans of the patient’s head, and using advanced medical segmentation software,  reconstructed in 3D the anatomical regions of interest of the patient applicable to the forthcoming malar surgery. The segmentation process involves the selection of the Hounsfield units (a measurement of radio density of the data received using a CT scan of the patient) corresponding to the appropriate bone areas of interest.

CMF Case Study 3 - Malar Symmetrisation Using Patient-Specific Onlay Implant 2
CMF Case Study 3 - Malar Symmetrisation Using Patient-Specific Onlay Implant 3

Virtual Simulation

The 3D reconstruction / segmentation of the patient’s anatomy from the CT scan was used to virtually plan the surgery in order to aid with the surgeon’s pre-surgical planning process. First, a mirror is created (the section shown in red).

The mirror is positioned to fit the infra orbital rim, the lateral orbital rim, and the zygomatic process as much as possible.

Design of Patient Specific Devices

The implant is designed based on the mirror. It fits perfectly the anatomy and is designed based on the surgeon’s requirement as well as the surgical approach and the type of screws used.

Once validated by the surgeon, the implant is 3D printed in titanium and shipped to the hospital. After sterilisation, the implant can be implanted in the patient.

CMF Case Study 3 - Malar Symmetrisation Using Patient-Specific Onlay Implant 4
CMF Case Study 3 - Malar Symmetrisation Using Patient-Specific Onlay Implant 5

Outcome

It is estimated that using traditional techniques for the creation of malar implants, 10 %  are removed or replaced because of improper implant size, shape or position.

The use of 3D technologies and the virtual planning simulation process enabled a highly accurate implant to be created and implanted that required no further adaption. The shape of the implant enabled the surgeon to easily position it through a transoral approach. Post surgery, the surgeon commented “It went really well. Fitted perfectly!”.