Manufacture of custom-made cranial implants from DICOM® images using 3D printing, CAD/CAM technology and incremental sheet forming

Abstract

Introduction: This work aims to pre-operatively manufacture custom-made low-cost implants and physical models ('biomodels') of fractured skulls. The pre-operative manufacturing of biomodels and implants allows physicians to study and plan surgery with a greater possibility of achieving the expected result. Customization contributes to both the esthetic and functional outcome of the implant because it considers the anatomy of each patient, while the low cost allows a greater number of people to potentially benefi t. Methods: From CT images of a fractured skull, a CAD model of the skull (biomodel) and a restorative implant were constructed digitally. The biomodel was then physically constructed with 3D Printing, and Incremental Sheet Forming (ISF) was used to manufacture the implant from a sheet of pure grade 2 titanium. Before cutting the implant's fi nal shape from a pre-formed sheet, heat treatment was performed to avoid deformations caused by residual stresses generated during the ISF process. Results: A comparison of the dimensions of the implant and its respective CAD biomodel revealed geometric discrepancies that can affect both functional and aesthetic effi ciency. Nevertheless, the fi nal shape preserved symmetry between the right and left sides of the skull. Electron microscopy analysis did not indicate the presence of elements other than pure titanium. Conclusions: Dimensional variability can be decreased with changes in the manufacturing process (i.e., forming and cutting) and the heating ramp. Despite biomedical characteristics, there was no contamination of the implant by harmful chemical elements. 3D Printing was effective in making the biomodel, enabling pre-operative planning and improving physicianpatient communication. Current results indicate that ISF is a process that can be used to obtain custom-made implants.

The use of single point incremental forming for customized implants of unicondylar knee arthroplasty: a review

“…The manufacturing of the custom-made cranial implants from Digital Image and Communications in Medicine (DICOM) images using 3D printing, CAD/CAM technology and incremental sheet forming was presented (Castelan et al, 2014). From CT images of a fractured skull, a CAD model of the skull (biomodel) and a restorative implant were constructed digitally.…”

“…The ISF process forms the component using stretching and bending while maintaining the material's crystal structure. The process can be performed using any 3-axis (and higher) Computer Numeric Controlled (CNC) machine, making it highly available and cost effective to the manufacturing industry (Araújo et al, 2013;Blaga, 2011;Castelan et al, 2009Castelan et al, , 2014Daleffe et al, 2013;Duflou et al, 2013;Eksteen and Van der Merwe, 2012;Henrard, 2008).…”

The Effect of 3d Printing Machine Parameters in Extrusion Process of Biocomposite Materials (Pmma and Ha) on Dimensional Accuracy

“…According to Saldarriaga et al (2011) in Castelan et al (2014, the use of manufacturing technologies such as 3D printing can reduce operating time by up to 85% (Köksal et al, 2011), restore the patient's body shape precisely as before, reduce errors in the operation process, avoid modification of the implant area around injury during operation, and the printed model can be used as an effective communication tool to the patient's family. These advantages make this technology intensively developed to achieve a good quality implant (Mohammed et al, 2016;Lamboni et al, 2015;Serbetci et al, 2004).…”

Improvement of Radial basis Function Interpolation Performance on Cranial Implant Design

“…Titanium was preferred as the implant material in the study since its high-strength characteristic. In the study, symmetrical data and CAD software were used to create the implant [13].…”