Prog Med Phys.  2019 Dec;30(4):155-159. 10.14316/pmp.2019.30.4.155.

Radiological Characteristics of Materials Used in 3-Dimensional Printing with Various Infill Densities

• Park SY
• Choi N
• Choi BG
• Lee DM
• Jang NY

• KMID: 2468177
• DOI: http://doi.org/10.14316/pmp.2019.30.4.155

Abstract

Radiological properties of newly introduced and existing 3-dimensional (3D) printing materials were evaluated by measuring their Hounsfield units (HUs) at varying infill densities. The six materials for 3D printing which consisted of acrylonitrile butadiene styrene (ABS), a unique ABS plastic blend manufactured by Zortrax (ULTRAT), high impact polystyrene (HIPS), polyethylene terephthalate glycol (PETG), polylactic acid (PLA), and a thermoplastic polyester elastomer manufactured by Zortrax (FLEX) were used. We used computed tomography (CT) imaging to determine the HU values of each material, and thus assess its suitability for various applications in radiation oncology. We found that several material and infill density combinations resembled the HU values of fat, soft tissues, and lungs; however, none of the tested materials exhibited HU values similar to that of bone. These results will help researchers and clinicians develop more appropriate instruments for improving the quality of radiation therapy. Using optimized infill densities will help improve the quality of radiation therapy by producing customized instruments for each field of radiation therapy.

Keyword

3D printing; Computed tomography; Hounsfield unit; Infill density; Radiation oncology

MeSH Terms

Acrylonitrile
Elastomers
Lung
Plastics
Polyesters
Polyethylene Terephthalates
Polystyrenes
Printing, Three-Dimensional*
Radiation Oncology
Styrene
Acrylonitrile
Elastomers
Plastics
Polyesters
Polyethylene Terephthalates
Polystyrenes
Styrene

Figure

• 

  Fig. 1 Printing settings in Z-Suite program to select the infill density values.

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  Fig. 2 (a) High impact polystyrene material with infill density values from 10% to 100% and (b) computed tomography (CT) images in coronal view obtained by the Brilliance CT Big Bore™.

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  Fig. 3 Correlations between Hounsfield unit (HUs) and infill density values for high impact polystyrene (HIPS) and polylactic acid (PLA) are plotted with dashed lines, respectively. Polynomial fitting curves for these correlations for HIPS and PLA are plotted with solid lines, respectively.

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