Using a 3D Printed Model as a Preoperative Tool for Pelvic Triple Osteotomy in Children: Proof of Concept and Evaluation of Geometric Accuracy

Literature has reported the successful use of 3D printed polyetheretherketone (PEEK) to fabricate human body implants and oral prostheses. However, the current 3D printed PEEK (brown color) cannot mimic the vivid color of oral tissues and thus cannot meet the esthetical need for dental application. Therefore, titanium dioxide (TiO2) and ferric oxide (Fe2O3) were incorporated into PEEK to prepare a series of tooth-color and gingival-color PEEK composites in this study. Through color measurements and mechanical tests, the color value and mechanical performance of the 3D printed PEEK composites were evaluated. In addition, duotone PEEK specimens were printed by a double nozzle with an interface between tooth-color and gingival-color parts. The mechanical performance of duotone PEEK with two different interfaces (horizontal and vertical) was investigated. With the addition of TiO2 and Fe2O3, the colors of 3D printed PEEK composites become closer to that of dental shade guides. 3D printed PEEK composites generally demonstrated superior tensile and flexural properties and hence have great potential in the dental application. In addition, duotone 3D printed PEEK with a horizontal interfacial orientation presented better mechanical performance than that with a vertical one.

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Rapid Production of PDMS Microdevices for Electrodriven Separations and Microfluidics by 3D-Printed Scaffold Removal

Separations ◽

10.3390/separations8050067 ◽

2021 ◽

Vol 8 (5) ◽

pp. 67

Author(s):

Alena Šustková ◽

Klára Konderlová ◽

Ester Drastíková ◽

Stefan Sützl ◽

Lenka Hárendarčíková ◽

...

Keyword(s):

Organic Dyes ◽

Microfluidic Devices ◽

Proof Of Concept ◽

Magnetic Microparticles ◽

Mechanical Removal ◽

Glass Slides ◽

Rapid Production ◽

3D Printed

In our work, we produced PDMS-based microfluidic devices by mechanical removal of 3D-printed scaffolds inserted in PDMS. Two setups leading to the fabrication of monolithic PDMS-based microdevices and bonded (or stamped) PDMS-based microdevices were designed. In the monolithic devices, the 3D-printed scaffolds were fully inserted in the PDMS and then carefully removed. The bonded devices were produced by forming imprints of the 3D-printed scaffolds in PDMS, followed by bonding the PDMS parts to glass slides. All these microfluidic devices were then successfully employed in three proof-of-concept applications: capture of magnetic microparticles, formation of droplets, and isotachophoresis separation of model organic dyes.

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A scalable mass customisation design process for 3D-printed respirator mask to combat COVID-19

Rapid Prototyping Journal ◽

10.1108/rpj-10-2020-0231 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Shiya Li ◽

Usman Waheed ◽

Mohanad Bahshwan ◽

Louis Zizhao Wang ◽

Livia Mariadaria Kalossaka ◽

...

Keyword(s):

Design Process ◽

Acquisition Time ◽

Geometric Accuracy ◽

Depth Sensor ◽

Content Type ◽

Mass Customisation ◽

Equipment Cost ◽

Cad Models ◽

3D Printed ◽

Acquisition Method

Purpose A three-dimensional (3D) printed custom-fit respirator mask has been proposed as a promising solution to alleviate mask-related injuries and supply shortages during COVID-19. However, creating a custom-fit computer-aided design (CAD) model for each mask is currently a manual process and thereby not scalable for a pandemic crisis. This paper aims to develop a novel design process to reduce overall design cost and time, thus enabling the mass customisation of 3D printed respirator masks. Design/methodology/approach Four data acquisition methods were used to collect 3D facial data from five volunteers. Geometric accuracy, equipment cost and acquisition time of each method were evaluated to identify the most suitable acquisition method for a pandemic crisis. Subsequently, a novel three-step design process was developed and scripted to generate respirator mask CAD models for each volunteer. Computational time was evaluated and geometric accuracy of the masks was evaluated via one-sided Hausdorff distance. Findings Respirator masks were successfully generated from all meshes, taking <2 min/mask for meshes of 50,000∼100,000 vertices and <4 min for meshes of ∼500,000 vertices. The average geometric accuracy of the mask ranged from 0.3 mm to 1.35 mm, depending on the acquisition method. The average geometric accuracy of mesh obtained from different acquisition methods ranged from 0.56 mm to 1.35 mm. A smartphone with a depth sensor was found to be the most appropriate acquisition method. Originality/value A novel and scalable mass customisation design process was presented, which can automatically generate CAD models of custom-fit respirator masks in a few minutes from a raw 3D facial mesh. Four acquisition methods, including the use of a statistical shape model, a smartphone with a depth sensor, a light stage and a structured light scanner were compared; one method was recommended for use in a pandemic crisis considering equipment cost, acquisition time and geometric accuracy.

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Closing the Loop - Recycling Plastic Waste

10.26686/wgtn.17145728.v1 ◽

2021 ◽

Author(s):

◽

Caitlin Bruce

Keyword(s):

New Zealand ◽

Additive Manufacturing ◽

Circular Economy ◽

Building Material ◽

New Technologies ◽

Plastic Waste ◽

Proof Of Concept ◽

Waste Production ◽

Closing The Loop ◽

3D Printed

<p>New Zealand is ranked among the top nations in waste production, including a million tonnes of plastic waste. Currently, there are methods for recycling plastic within New Zealand but these methods can be expensive and time-consuming, resulting in most of the plastic being thrown into the landfill. Because plastic does not fully degrade, it ends up in the ocean and other waterways, poisoning the water with toxins. The purpose of this research is to provide a solution to reducing plastic waste by creating an alternative method of recycling that utilises new technologies such as additive manufacturing, to create a building material that fits into the concept of the circular economy. The findings of this research explored the recycling of plastic by collecting plastic waste such as PLA (Polylactic Acid) from old 3D printed models. The plastic was recycled into filament for additive manufacturing (AM) and used to print building tile, establishing an initial proof of concept for the use of recycled plastic as a potential building material.</p>

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Proof-of-concept for a segmented composite diving suit offering depth-independent thermal protection

Diving and Hyperbaric Medicine Journal ◽

10.28920/dhm51.3.295-298 ◽

2021 ◽

Vol 51 (3) ◽

pp. 295-298

Author(s):

Aaron Demers ◽

◽

Shane Martin ◽

Emil P Kartalov ◽

◽

...

Keyword(s):

Thermal Protection ◽

Health Hazard ◽

Organ Damage ◽

Field Trials ◽

Proof Of Concept ◽

Major Health ◽

3D Printed ◽

Higher Temperature ◽

3D Scans ◽

Resistive Composite

Heat loss is a major health hazard for divers. It can lead to hypothermia, organ damage, unconsciousness, and eventually death. Hence, thermal protection is essential for diver safety. Typically, protection is provided by wetsuits made of bubbled neoprene. However, neoprene shrinks with depth and loses thermal insulation capability, while thick neoprene suits make swimming exhausting. Herein, a proof-of-concept is presented for a solution to both problems: a ‘K-suit’ made of thermally-resistive composite segments attached to a thin neoprene suit. The segments are made of hollow glass microspheres embedded in carrier polymer thermally cured in 3D-printed molds based on 3D-scans of the diver’s body. The K-suit was compared in field trials with a 7 mm commercial neoprene suit by diving in pairs, while automated dataloggers registered pressure and temperature inside and outside both suits. The K-suit demonstrated +4ºC higher temperature difference than the 7 mm neoprene. Also, divers reported that the K-suit had the ergonomics of a 3 mm neoprene suit. These preliminary results represent a proof-of-concept for the K-suit and promise further improvements with potential impact on diver safety.

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Enhancing X-ray Attenuation of 3D Printed Gelatin Methacrylate (GelMA) Hydrogels Utilizing Gold Nanoparticles for Bone Tissue Engineering Applications

Polymers ◽

10.3390/polym11020367 ◽

2019 ◽

Vol 11 (2) ◽

pp. 367 ◽

Cited By ~ 9

Author(s):

Nehar Celikkin ◽

Simone Mastrogiacomo ◽

X. Walboomers ◽

Wojciech Swieszkowski

Keyword(s):

Tissue Engineering ◽

Gold Nanoparticles ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Biological Properties ◽

Proof Of Concept ◽

New Bone Formation ◽

X Ray ◽

3D Printed ◽

Low Toxicity

Bone tissue engineering is a rapidly growing field which is currently progressing toward clinical applications. Effective imaging methods for longitudinal studies are critical to evaluating the new bone formation and the fate of the scaffolds. Computed tomography (CT) is a prevailing technique employed to investigate hard tissue scaffolds; however, the CT signal becomes weak in mainly-water containing materials, which hinders the use of CT for hydrogels-based materials. Nevertheless, hydrogels such as gelatin methacrylate (GelMA) are widely used for tissue regeneration due to their optimal biological properties and their ability to induce extracellular matrix formation. To date, gold nanoparticles (AuNPs) have been suggested as promising contrast agents, due to their high X-ray attenuation, biocompatibility, and low toxicity. In this study, the effects of different sizes and concentrations of AuNPs on the mechanical properties and the cytocompatibility of the bulk GelMA-AuNPs scaffolds were evaluated. Furthermore, the enhancement of CT contrast with the cytocompatible size and concentration of AuNPs were investigated. 3D printed GelMA and GelMA-AuNPs scaffolds were obtained and assessed for the osteogenic differentiation of mesenchymal stem cells (MSC). Lastly, 3D printed GelMA and GelMA-AuNPs scaffolds were scanned in a bone defect utilizing µCT as the proof of concept that the GelMA-AuNPs are good candidates for bone tissue engineering with enhanced visibility for µCT imaging.

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A novel ‘surgeon-dominated’ approach to the design of 3D-printed patient-specific surgical plates in mandibular reconstruction: a proof-of-concept study

International Journal of Oral and Maxillofacial Surgery ◽

10.1016/j.ijom.2019.05.005 ◽

2020 ◽

Vol 49 (1) ◽

pp. 13-21 ◽

Cited By ~ 9

Author(s):

W.-f. Yang ◽

C.-y. Zhang ◽

W.S. Choi ◽

W.-y. Zhu ◽

D.T.S. Li ◽

...

Keyword(s):

Mandibular Reconstruction ◽

Patient Specific ◽

Proof Of Concept ◽

Concept Study ◽

3D Printed

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Geometric Accuracy Prediction for Additive Manufacturing Through Machine Learning of Triangular Mesh Data

Volume 1: Additive Manufacturing; Manufacturing Equipment and Systems; Bio and Sustainable Manufacturing ◽

10.1115/msec2019-3050 ◽

2019 ◽

Cited By ~ 4

Author(s):

Nathan Decker ◽

Qiang Huang

Keyword(s):

Machine Learning ◽

Additive Manufacturing ◽

Three Dimensional ◽

Triangular Mesh ◽

Geometric Accuracy ◽

New Approach ◽

Machine Learning Model ◽

3D Printed ◽

3D Shapes ◽

Complex Parts

Abstract While additive manufacturing has seen tremendous growth in recent years, a number of challenges remain, including the presence of substantial geometric differences between a three dimensional (3D) printed part, and the shape that was intended. There are a number of approaches for addressing this issue, including statistical models that seek to account for errors caused by the geometry of the object being printed. Currently, these models are largely unable to account for errors generated in freeform 3D shapes. This paper proposes a new approach using machine learning with a set of predictors based on the geometric properties of the triangular mesh file used for printing. A direct advantage of this method is the simplicity with which it can describe important properties of a 3D shape and allow for predictive modeling of dimensional inaccuracies for complex parts. To evaluate the efficacy of this approach, a sample dataset of 3D printed objects and their corresponding deviations was generated. This dataset was used to train a random forest machine learning model and generate predictions of deviation for a new object. These predicted deviations were found to compare favorably to the actual deviations, demonstrating the potential of this approach for applications in error prediction and compensation.

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Comparison of Flexible 3D Printed Stenotic Airway Model Versus Standard Model for Therapeutic Bronchoscopy Training a Proof of Concept

Journal of Bronchology & Interventional Pulmonology ◽

10.1097/lbr.0000000000000701 ◽

2020 ◽

Vol Publish Ahead of Print ◽

Author(s):

Alex Chee ◽

Melibea Sierra-Ruiz ◽

Mihir S. Parikh ◽

Adnan Majid

Keyword(s):

Standard Model ◽

Proof Of Concept ◽

3D Printed ◽

Model Versus ◽

Airway Model

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Multi-Material 3D Printing of a Customized Sports Mouth Guard: Proof-of-Concept Clinical Case

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph182312762 ◽

2021 ◽

Vol 18 (23) ◽

pp. 12762

Author(s):

Alexey Unkovskiy ◽

Fabian Huettig ◽

Pablo Kraemer-Fernandez ◽

Sebastian Spintzyk

Keyword(s):

3D Printing ◽

Free Form ◽

Proof Of Concept ◽

Virtual Design ◽

Digital Workflow ◽

Protective Function ◽

Drop On Demand ◽

3D Printed ◽

Mouth Guards ◽

Protective Performance

A multilayer mouth guard is known to have the best protective performance. However, its manufacturing in a digital workflow may be challenging with regards to virtual design and materialization. The present case demonstrates a pathway to fabricate a multilayer individualized mouth guard in a fully digital workflow, which starts with intraoral scanning. A free-form CAD software was used for the virtual design. Two various CAM techniques were used, including Polyjet 3D printing of rubber-like soft material and silicone printing using Drop-on-Demand technique. For both methods the outer layer was manufactured from more rigid materials to facilitate its protective function; the inner layer was printed from a softer material to aid a better adaptation to mucosa and teeth. Both 3D printed multilayer mouth guards showed a clinically acceptable fit and were met with patient appraisal. Their protective capacities must be evaluated in further clinical studies.

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