Dimensional accuracy and reproducibility of three different methods of 3D printing using a known size object

Abstract

Objective: To assess the accuracy and reproducibility of FDM (Cubicon Single Plus, Cubicon Inc., Korea) and Polyjet (Objet Eden 250, Stratasys Ltd., USA) 3D printers, by comparing linear dimensions between 3D models, printed using photocurable resin (RGD720 & SUP705, Stratasys Ltd., USA), ABS and PLA (Cubicon Inc., Korea), and the original 3D image, to establish which one is more accurate and cost-effective.

Methodology: An irregular cube was designed using Autodesk Fusion 360 software and exported as an STL file; 10 cubes of each material were printed and measured in 8 allocated dimensions and their 4 corners. These measurements were compared to the dimensions of the original 3D image and accuracy was evaluated according to the dimensional differences between the models and the 3D image.

Results: There was a highly significant difference between resin and ABS, and between ABS and PLA; this difference was not clinically acceptable. On the other hand, there was no significant difference between resin and PLA, and both materials are considered clinically acceptable.

Conclusion: Both Polyjet’s resin and FDM’s PLA are equally accurate, therefore, the selection of the manufacturing method would depend on the clinical use of the printed object. Polyjet’s resin can be recommended for the fabrication of surgical guides and to shape medical devices like fixation plates, as higher surface details and mechanical properties are required. FDM’s PLA can be suggested for the fabrication of models for surgical simulation, treatment planning and patient education, as it is equally accurate and more cost-effective than resin.

Date of Award	25 Sept 2020
Original language	English
Awarding Institution	King's College London
Supervisor	Trevor Coward (Supervisor)