Mechanical and medical imaging properties of 3D‐printed materials as tissue equivalent materials

Abstract

Three materials of polylactic acid (PLA), polyamide 12 (PA12), and light curing resin (LCR) were used to construct phantom using 3D printing technology. The mechanical and medical imaging properties of the three materials, such as elastic modulus, density, effective atomic number, X‐ray attenuation coefficient, computed tomography (CT) number, and acoustic properties, were investigated. The results showed that the elastic modulus for PLA was 1.98 × 103 MPa, for PA12 was 848 MPa, for LCR was 1.18×103 MPa, and that of three materials was close to some bones. In the range of 40∼120 kV, the X‐ray attenuation coefficient of three materials decreased with increasing tube voltage. The CT number for PLA, PA12, and LCR was 144, −88, and 312 Hounsfield units at 120 kV tube voltage, respectively. The density and the effective atomic number product (ρ*Zeff) were computed from three materials and decreased in the order of LCR, PLA, and PA12. The acoustic properties of materials were also studied. The speeds of sound of three materials were similar with those of some soft tissues.

Methodology for computed tomography characterization of commercially available 3D printing materials for use in radiology/radiation oncology

“…28 Previous studies have characterized 3D print materials using kilovoltage CT similar to the methods in this work. [7][8][9][11][12][13]15,16,19,21 However, the work presented herein builds upon past efforts in multiple ways. This work focuses on readily and commercially available filaments, most of which have not yet been characterized.…”

“…In radiotherapy, additive manufacturing has already been used to create compensators, phantoms, shielding, and other innovative solutions to improve standard practices 5,23 . In phantom production, the need to become more tissue equivalent is being explored and this examination of commercially available materials will allow for radiological properties to be replicated more thoroughly 21 . The replication of tissues for use in dosimetry has been successfully used in rapid prototyping within radiotherapy 26 .…”

“…12,13,19 The growing literature on this subject will help to find more applications and wider utility for 3D printing in radiology and radiation oncology. However, there is wide variability in printing techniques, measurement approaches, filament compositions (by manufacturer and by specific filament batch), as well as how printed components will be used (radiography/mammography, 10,14,[16][17][18]20,21 kilovoltage CT of various energies, 8,9,11,12,15,19,21,22 megavoltage applications such as MVCT or radiotherapy dosimetry, 6,7,12,13 or for exogenous components (e.g., bolus, orthopedic implants, brachytherapy applicators, etc.). 2,3 This work seeks to comprehensively evaluate commercially available 3D printing filaments with nonstandard composition for use in reproducing Hounsfield units (HUs) at various peak kilovoltage (kVp) spanning the range of all expected human tissues (from lung to dense bone) as well as even higher-density/higher-Z metallic implants.…”

“…The growing literature on this subject will help to find more applications and wider utility for 3D printing in radiology and radiation oncology. However, there is wide variability in printing techniques, measurement approaches, filament compositions (by manufacturer and by specific filament batch), as well as how printed components will be used (radiography/mammography, 10,14,16–18,20,21 kilovoltage CT of various energies, 8,9,11,12,15,19,21,22 megavoltage applications such as MVCT or radiotherapy dosimetry, 6,7,12,13 or for exogenous components (e.g., bolus, orthopedic implants, brachytherapy applicators, etc.) 2,3 .…”

An Overview of Extracellular Matrix-Based Bioinks for 3D Bioprinting

“…3D printing can quickly fabricate various structures with little waste of material. Coupled with the gradual reduction of the cost and personalized customization, 3D printing has become widely used in many fields, especially in medical fields, such as tissue engineering ( Ma et al, 2022 ). Thus, 3D bioprinting came into being.…”