Freeform 3D-Printing of Pure Ceramics

Abstract Polymer derived ceramics (PDC’s) offer a unique opportunity to 3D-print ceramics; however, 3D printing of such polymers require it to be combined with specialized light-sensitive agents and layer-by-layer crosslinking using an optical beam due to their low viscosity. Here, three-dimensional printing of ceramics enabled by dispensing the preceramic polymer from a nozzle inside a yield stress fluid is being demonstrated. The printed parts are crosslinked in the same gel. After crosslinking process, the printed parts are taken out of the gel and prepared for high temperature pyrolysis process that converts the cured parts to ceramic. The specially designed gel was three orders of magnitude more viscous than the preceramic polymer at no shear, which provided a stable medium during the whole process for maintaining the shape of the printed material and prevented possible instabilities. The SEM images of the cross section of the specimens showed that the printed material was dense and without any apparent porosity or cracks. Statistical analysis on the mechanical properties of the printed preceramic polymer specimens revealed that the printed specimens had characteristic strength (∼257 MPa).

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THE POSSIBILITY OF THREE-DIMENSIONAL PRINTING WITH SILICATE MASSES USING CERAMIC AND HYDRATION BINDERS

Bulletin of Belgorod State Technological University named after V G Shukhov ◽

10.34031/2071-7318-2021-6-1-74-81 ◽

2021 ◽

Vol 6 (1) ◽

pp. 74-81

Author(s):

I. Moreva ◽

T. Varenikova ◽

N. Kirillova ◽

V. Doroganov ◽

M. Lebedev ◽

...

Keyword(s):

3D Printing ◽

Low Cost ◽

Slip Casting ◽

Three Dimensional ◽

Layer By Layer ◽

Three Dimensional Printing ◽

High Productivity ◽

Long Time ◽

Energy Consuming ◽

Production Technologies

The 3D printing technologies have appeared for a long time and are successfully used in a number of industries. The activities of many leading companies in the creation of layouts, models and prototypes of units, assemblies, products are practically not carried out without the use of 3D printing. The following are batch production technologies with high productivity combined with low cost, comparable to traditional methods of manufacturing products. The production of various products from silicate masses in an additive manner is seriously constrained by a number of issues due to the specifics of the material itself. One of them - achieving high physical and mechanical characteristics is possible only after hydration (for cements) or heat treatment (ceramic masses) of the product. Significant influence is exerted by the method of manufacturing the product. The most convenient and least energy-consuming method (in comparison with the powder 3D printing methods using laser sintering) is layer-by-layer slip casting or plastic extrusion, however, there are some unresolved problems. This paper highlights the key problems of using the additive method of manufacturing structural products on ceramic and hydration bonds using plastic and rigid masses in combination with vibration effects.

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Traditional versus mirror three-dimensional printing technology for isolated acetabular fractures: a retrospective study with a median follow-up of 25 months

Journal of International Medical Research ◽

10.1177/03000605211028554 ◽

2021 ◽

Vol 49 (6) ◽

pp. 030006052110285

Author(s):

Kai Xiao ◽

Bo Xu ◽

Lin Ding ◽

Weiguang Yu ◽

Lei Bao ◽

...

Keyword(s):

3D Printing ◽

Three Dimensional ◽

Operation Time ◽

Harris Hip Score ◽

Acetabular Fractures ◽

Printing Technology ◽

Three Dimensional Printing ◽

3D Printing Technology ◽

Significant Difference

Objective To assess the outcomes of traditional three-dimensional (3D) printing technology (TPT) versus mirror 3D printing technology (MTT) in treating isolated acetabular fractures (IAFs). Methods Consecutive patients with an IAF treated by either TPT or MTT at our tertiary medical centre from 2012 to 2018 were retrospectively reviewed. Follow-up was performed 1, 3, 6, and 12 months postoperatively and annually thereafter. The primary outcome was the Harris hip score (HHS), and the secondary outcomes were major intraoperative variables and key orthopaedic complications. Results One hundred fourteen eligible patients (114 hips) with an IAF (TPT, n = 56; MTT, n = 58) were evaluated. The median follow-up was 25 months (range, 21–28 months). At the last follow-up, the mean HHS was 82.46 ±14.70 for TPT and 86.30 ± 13.26 for MTT with a statistically significant difference. Significant differences were also detected in the major intraoperative variables (operation time, intraoperative blood loss, number of fluoroscopic screenings, and anatomical reduction number) and the major orthopaedic complications (loosening, implant failure, and heterotopic ossification). Conclusion Compared with TPT, MTT tends to produce accurate IAF reduction and may result in better intraoperative variables and a lower rate of major orthopaedic complications.

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Three-dimensional printing for heart diseases: clinical application review

Bio-Design and Manufacturing ◽

10.1007/s42242-021-00125-8 ◽

2021 ◽

Author(s):

Yanyan Ma ◽

Peng Ding ◽

Lanlan Li ◽

Yang Liu ◽

Ping Jin ◽

...

Keyword(s):

3D Printing ◽

Clinical Application ◽

Heart Diseases ◽

Three Dimensional ◽

Convincing Evidence ◽

Surgical Interventions ◽

Three Dimensional Printing ◽

Complex Anatomy ◽

Precise Understanding ◽

3D Printed

AbstractHeart diseases remain the top threat to human health, and the treatment of heart diseases changes with each passing day. Convincing evidence shows that three-dimensional (3D) printing allows for a more precise understanding of the complex anatomy associated with various heart diseases. In addition, 3D-printed models of cardiac diseases may serve as effective educational tools and for hands-on simulation of surgical interventions. We introduce examples of the clinical applications of different types of 3D printing based on specific cases and clinical application scenarios of 3D printing in treating heart diseases. We also discuss the limitations and clinically unmet needs of 3D printing in this context.

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A guideline for 3D printing terminology in biomedical research utilizing ISO/ASTM standards

3D Printing in Medicine ◽

10.1186/s41205-021-00098-5 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Amy E. Alexander ◽

Nicole Wake ◽

Leonid Chepelev ◽

Philipp Brantner ◽

Justin Ryan ◽

...

Keyword(s):

3D Printing ◽

Medical Literature ◽

Three Dimensional ◽

Physical Object ◽

Medical Community ◽

Layer By Layer ◽

Digital File ◽

Standardized Terminology ◽

Standard Terms ◽

The Impact

AbstractFirst patented in 1986, three-dimensional (3D) printing, also known as additive manufacturing or rapid prototyping, now encompasses a variety of distinct technology types where material is deposited, joined, or solidified layer by layer to create a physical object from a digital file. As 3D printing technologies continue to evolve, and as more manuscripts describing these technologies are published in the medical literature, it is imperative that standardized terminology for 3D printing is utilized. The purpose of this manuscript is to provide recommendations for standardized lexicons for 3D printing technologies described in the medical literature. For all 3D printing methods, standard general ISO/ASTM terms for 3D printing should be utilized. Additional, non-standard terms should be included to facilitate communication and reproducibility when the ISO/ASTM terms are insufficient in describing expository details. By aligning to these guidelines, the use of uniform terms for 3D printing and the associated technologies will lead to improved clarity and reproducibility of published work which will ultimately increase the impact of publications, facilitate quality improvement, and promote the dissemination and adoption of 3D printing in the medical community.

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Three-Dimensional Printing of Hydroxyapatite Composites for Biomedical Application

Crystals ◽

10.3390/cryst11040353 ◽

2021 ◽

Vol 11 (4) ◽

pp. 353

Author(s):

Yanting Han ◽

Qianqian Wei ◽

Pengbo Chang ◽

Kehui Hu ◽

Oseweuba Valentine Okoro ◽

...

Keyword(s):

Tissue Engineering ◽

3D Printing ◽

Biomedical Application ◽

Three Dimensional ◽

Antibacterial Properties ◽

Natural Polymers ◽

Three Dimensional Printing ◽

3D Printed ◽

Dental Applications ◽

Hard Tissue Engineering

Hydroxyapatite (HA) and HA-based nanocomposites have been recognized as ideal biomaterials in hard tissue engineering because of their compositional similarity to bioapatite. However, the traditional HA-based nanocomposites fabrication techniques still limit the utilization of HA in bone, cartilage, dental, applications, and other fields. In recent years, three-dimensional (3D) printing has been shown to provide a fast, precise, controllable, and scalable fabrication approach for the synthesis of HA-based scaffolds. This review therefore explores available 3D printing technologies for the preparation of porous HA-based nanocomposites. In the present review, different 3D printed HA-based scaffolds composited with natural polymers and/or synthetic polymers are discussed. Furthermore, the desired properties of HA-based composites via 3D printing such as porosity, mechanical properties, biodegradability, and antibacterial properties are extensively explored. Lastly, the applications and the next generation of HA-based nanocomposites for tissue engineering are discussed.

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Three-dimensionally printed polycaprolactone/multicomponent bioactive glass scaffolds for potential application in bone tissue engineering

Biomedical glasses ◽

10.1515/bglass-2020-0006 ◽

2020 ◽

Vol 6 (1) ◽

pp. 57-69

Author(s):

Amirhosein Fathi ◽

Farzad Kermani ◽

Aliasghar Behnamghader ◽

Sara Banijamali ◽

Masoud Mozafari ◽

...

Keyword(s):

Tissue Engineering ◽

3D Printing ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Three Dimensional ◽

Layer By Layer ◽

Composite Scaffolds ◽

3D Printed ◽

Co Doped

AbstractOver the last years, three-dimensional (3D) printing has been successfully applied to produce suitable substitutes for treating bone defects. In this work, 3D printed composite scaffolds of polycaprolactone (PCL) and strontium (Sr)- and cobalt (Co)-doped multi-component melt-derived bioactive glasses (BGs) were prepared for bone tissue engineering strategies. For this purpose, 30% of as-prepared BG particles (size <38 μm) were incorporated into PCL, and then the obtained composite mix was introduced into a 3D printing machine to fabricate layer-by-layer porous structures with the size of 12 × 12 × 2 mm3.The scaffolds were fully characterized through a series of physico-chemical and biological assays. Adding the BGs to PCL led to an improvement in the compressive strength of the fabricated scaffolds and increased their hydrophilicity. Furthermore, the PCL/BG scaffolds showed apatite-forming ability (i.e., bioactivity behavior) after being immersed in simulated body fluid (SBF). The in vitro cellular examinations revealed the cytocompatibility of the scaffolds and confirmed them as suitable substrates for the adhesion and proliferation of MG-63 osteosarcoma cells. In conclusion, 3D printed composite scaffolds made of PCL and Sr- and Co-doped BGs might be potentially-beneficial bone replacements, and the achieved results motivate further research on these materials.

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Porous PLAs with Controllable Density by FDM 3D Printing and Chemical Foaming Agent

Micromachines ◽

10.3390/mi12080866 ◽

2021 ◽

Vol 12 (8) ◽

pp. 866

Author(s):

A. R. Damanpack ◽

André Sousa ◽

M. Bodaghi

Keyword(s):

3D Printing ◽

Flow Rate ◽

Three Dimensional ◽

Poly Lactic Acid ◽

Layer By Layer ◽

Printing Technology ◽

Material Density ◽

Foaming Agent ◽

3D Printing Technology ◽

Fabrication Parameters

This paper shows how fused decomposition modeling (FDM), as a three-dimensional (3D) printing technology, can engineer lightweight porous foams with controllable density. The tactic is based on the 3D printing of Poly Lactic Acid filaments with a chemical blowing agent, as well as experiments to explore how FDM parameters can control material density. Foam porosity is investigated in terms of fabrication parameters such as printing temperature and flow rate, which affect the size of bubbles produced during the layer-by-layer fabrication process. It is experimentally shown that printing temperature and flow rate have significant effects on the bubbles’ size, micro-scale material connections, stiffness and strength. An analytical equation is introduced to accurately simulate the experimental results on flow rate, density, and mechanical properties in terms of printing temperature. Due to the absence of a similar concept, mathematical model and results in the specialized literature, this paper is likely to advance the state-of-the-art lightweight foams with controllable porosity and density fabricated by FDM 3D printing technology.

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Comparison of the internal fit of metal crowns fabricated by traditional casting, computer numerical control milling, and three-dimensional printing

PLoS ONE ◽

10.1371/journal.pone.0257158 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257158

Author(s):

Wei-Ting Chou ◽

Chuan-Chung Chuang ◽

Yi-Bing Wang ◽

Hsien-Chung Chiu

Keyword(s):

3D Printing ◽

Minimum Distance ◽

Statistical Significance ◽

Three Dimensional ◽

Reference Points ◽

Numerical Control ◽

Maximum Distance ◽

Cnc Milling ◽

Low Viscosity ◽

Internal Fit

This experimental study aimed to compare the internal fit (marginal fit and internal discrepancy) of metal crowns fabricated by traditional casting and digital methods (computer numerically controlled (CNC) milling and three-dimensional [3D] printing). Thirty standard master abutment models were fabricated using a 3D printing technique with digital software. Metal crowns were fabricated by traditional casting, CNC milling, and 3D printing. The silicon replica method was used to measure the marginal and internal fit. A thin layer of low-viscosity polyvinyl siloxane material was placed inside each crown and on the die (like a seat) until the material was set. Replicas were examined at four reference points under a microscope: the central pit (M1), cusp tip (M2), axial wall (M3), and margin (M4). The measured data were analyzed using a one-way analysis of variance (ANOVA) to verify statistical significance, which was set at p < 0.05. In the traditional casting group, the minimum distance measured was at M3 (90.68 ± 14.4 μm) and the maximum distance measured was at M1 (145.12 ± 22 μm). In the milling group, the minimum distance measured was at M3 (71.85 ± 23.69 μm) and the maximum distance measured was at M1 (108.68 ± 10.52 μm). In the 3D printing group, the minimum distance measured was at M3 (100.59 ± 9.26 μm) and the maximum distance measured was at M1 (122.33 ± 7.66 μm). The mean discrepancy for the traditional casting, CNC milling, and 3D printing groups was 120.20, 92.15, and 111.85 μm, respectively, showing significant differences (P < 0.05). All three methods of metal crown fabrication, that is, traditional casting, CNC milling, and 3D printing, had values within the clinically acceptable range. The marginal and internal fit of the crown was far superior in the CNC milling method.

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A Review on Development of Bio-Inspired Implants Using 3D Printing

Biomimetics ◽

10.3390/biomimetics6040065 ◽

2021 ◽

Vol 6 (4) ◽

pp. 65

Author(s):

Ansheed A. Raheem ◽

Pearlin Hameed ◽

Ruban Whenish ◽

Renold S. Elsen ◽

Aswin G ◽

...

Keyword(s):

Additive Manufacturing ◽

3D Printing ◽

Layer By Layer ◽

Medical Implants ◽

3D Print ◽

Metal Implants ◽

Natural Tissue ◽

And Control ◽

Natural Architecture ◽

Fine Tune

Biomimetics is an emerging field of science that adapts the working principles from nature to fine-tune the engineering design aspects to mimic biological structure and functions. The application mainly focuses on the development of medical implants for hard and soft tissue replacements. Additive manufacturing or 3D printing is an established processing norm with a superior resolution and control over process parameters than conventional methods and has allowed the incessant amalgamation of biomimetics into material manufacturing, thereby improving the adaptation of biomaterials and implants into the human body. The conventional manufacturing practices had design restrictions that prevented mimicking the natural architecture of human tissues into material manufacturing. However, with additive manufacturing, the material construction happens layer-by-layer over multiple axes simultaneously, thus enabling finer control over material placement, thereby overcoming the design challenge that prevented developing complex human architectures. This review substantiates the dexterity of additive manufacturing in utilizing biomimetics to 3D print ceramic, polymer, and metal implants with excellent resemblance to natural tissue. It also cites some clinical references of experimental and commercial approaches employing biomimetic 3D printing of implants.

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Transfiguring Healthcare: Three-Dimensional Printing in Pharmaceutical Sciences; Trends during COVID-19: A Review

Journal of Pharmaceutical Research International ◽

10.9734/jpri/2021/v33i56b33946 ◽

2021 ◽

pp. 207-218

Author(s):

K. G. Siree ◽

T. M. Amulya ◽

T. M. Pramod Kumar ◽

S. Sowmya ◽

K. Divith ◽

...

Keyword(s):

3D Printing ◽

Medical Devices ◽

Three Dimensional ◽

Pharmaceutical Sciences ◽

Three Dimensional Printing ◽

Custom Made ◽

High Degree ◽

The Impact ◽

Dimensional Printing ◽

Shed Light

Three-dimensional (3D) printing is a unique technique that allows for a high degree of customisation in pharmacy, dentistry and in designing of medical devices. 3D printing satiates the increasing exigency for consumer personalisation in these fields as custom-made medicines catering to the patients’ requirements are novel advancements in drug therapy. Current research in 3D printing indicates towards reproducing an organ in the form of a chip; paving the way for more studies and opportunities to perfecting the existing technique. In addition, we will also attempt to shed light on the impact of 3D printing in the COVID-19 pandemic.

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