Reproducibility of linear measurements performed in dental models from 3D printing

This study aimed to assess the reproducibility of linear measurements performed in dental models produced via intraoral scanning and three-dimensional (3D) printing using digital light processing (DLP) and fused deposition modeling (FDM). A sample of 22 participants was selected for this study. Intraoral scanning was performed in each participant with TRIOS™ (3Shape A/S™, Copenhagen, Denmark) device. The digital models were 3D printed using DLP and FDM techniques. Using a caliper, intraoral linear measurements were performed in situ (on the surface of participant’s teeth) and on the 3D printed models. The measurements taken intraoral and on the models were compared using the Intraclass Correlation Coefficient (ICC). The correlation between measurements taken in situ and on DLP models was poor (<0.4), while between in situ and FDM it ranged from poor to satisfactory (<0.75). Generalized linear model showed that the differences did not reach statistically significant levels (p>0.05). According to Bland-Altman approach, the size of measurements did not bias the outcomes. The intraoral scanning and 3D printing techniques used in this study enabled the reproducibility of linear measurements, however, discrete distortions that might be clinically significant occurred.

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Biodegradable 3D Printed Polymer Microneedles for Transdermal Drug Delivery

10.26434/chemrxiv.5851950.v1 ◽

2018 ◽

Cited By ~ 1

Author(s):

Michael A. Luzuriaga ◽

Danielle R. Berry ◽

John C. Reagan ◽

Ronald A. Smaldone ◽

Jeremiah J. Gassensmith

Keyword(s):

Drug Delivery ◽

3D Printing ◽

Transdermal Drug Delivery ◽

Fused Deposition Modeling ◽

Fused Deposition ◽

Modeling Software ◽

Deposition Modeling ◽

3D Printed ◽

Microfabrication Technique ◽

Mechanical Strengths

Biodegradable polymer microneedle (MN) arrays are an emerging class of transdermal drug delivery devices that promise a painless and sanitary alternative to syringes; however, prototyping bespoke needle architectures is expensive and requires production of new master templates. Here, we present a new microfabrication technique for MNs using fused deposition modeling (FDM) 3D printing using polylactic acid, an FDA approved, renewable, biodegradable, thermoplastic material. We show how this natural degradability can be exploited to overcome a key challenge of FDM 3D printing, in particular the low resolution of these printers. We improved the feature size of the printed parts significantly by developing a post fabrication chemical etching protocol, which allowed us to access tip sizes as small as 1 μm. With 3D modeling software, various MN shapes were designed and printed rapidly with custom needle density, length, and shape. Scanning electron microscopy confirmed that our method resulted in needle tip sizes in the range of 1 – 55 µm, which could successfully penetrate and break off into porcine skin. We have also shown that these MNs have comparable mechanical strengths to currently fabricated MNs and we further demonstrated how the swellability of PLA can be exploited to load small molecule drugs and how its degradability in skin can release those small molecules over time.

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Mechanical Characterization and Thermodynamic Analysis of Laser-Polished Landscape Design Products Using 3D Printing

Materials ◽

10.3390/ma14102601 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2601

Author(s):

Yue Ba ◽

Yu Wen ◽

Shibin Wu

Keyword(s):

Surface Roughness ◽

3D Printing ◽

Fused Deposition Modeling ◽

High Surface ◽

Landscape Design ◽

Laser Polishing ◽

Fused Deposition ◽

Design Structure ◽

3D Printed ◽

Stability And Accuracy

Recent innovations in 3D printing technologies and processes have influenced how landscape products are designed, built, and developed. In landscape architecture, reduced-size models are 3D-printed to replicate full-size structures. However, high surface roughness usually occurs on the surfaces of such 3D-printed components, which requires additional post-treatment. In this work, we develop a new type of landscape design structure based on the fused deposition modeling (FDM) technique and present a laser polishing method for FDM-fabricated polylactic acid (PLA) mechanical components, whereby the surface roughness of the laser-polished surfaces is reduced from over Ra 15 µm to less than 0.25 µm. The detailed results of thermodynamics and microstructure evolution are further analyzed during laser polishing. The stability and accuracy of the results are evaluated based on the standard deviation. Additionally, the superior tensile and flexural properties are examined in the laser-polished layer, in which the ultimate tensile strength (UTS) is increased by up to 46.6% and the flexural strength is increased by up to 74.5% compared with the as-fabricated components. Finally, a real polished landscape model is simulated and optimized using a series of scales.

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3D Printed Clamps for In Vitro Tensile Tests of Human Gracilis and the Superficial Third of Quadriceps Tendons

Applied Sciences ◽

10.3390/app11062563 ◽

2021 ◽

Vol 11 (6) ◽

pp. 2563

Author(s):

Ivan Grgić ◽

Vjekoslav Wertheimer ◽

Mirko Karakašić ◽

Željko Ivandić

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Tensile Tests ◽

Biomechanical Properties ◽

Testing Procedure ◽

Laboratory Equipment ◽

Fused Deposition ◽

Custom Made ◽

3D Printed

Recent soft tissue studies have reported issues that occur during experimentation, such as the tissue slipping and rupturing during tensile loads, the lack of standard testing procedure and equipment, the necessity for existing laboratory equipment adaptation, etc. To overcome such issues and fulfil the need for the determination of the biomechanical properties of the human gracilis and the superficial third of the quadriceps tendons, 3D printed clamps with metric thread profile-based geometry were developed. The clamps’ geometry consists of a truncated pyramid pattern, which prevents the tendons from slipping and rupturing. The use of the thread application in the design of the clamp could be used in standard clamping development procedures, unlike in previously custom-made clamps. Fused deposition modeling (FDM) was used as a 3D printing technique, together with polylactic acid (PLA), which was used as a material for clamp printing. The design was confirmed and the experiments were conducted by using porcine and human tendons. The findings justify the usage of 3D printing technology for parts manufacturing in the case of tissue testing and establish independence from the existing machine clamp system, since it was possible to print clamps for each prepared specimen and thus reduce the time for experiment setup.

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3D Printing of Thermo-Sensitive Drugs

Pharmaceutics ◽

10.3390/pharmaceutics13091524 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1524

Author(s):

Sadikalmahdi Abdella ◽

Souha H. Youssef ◽

Franklin Afinjuomo ◽

Yunmei Song ◽

Paris Fouladian ◽

...

Keyword(s):

3D Printing ◽

Three Dimensional ◽

Fused Deposition Modelling ◽

Future Directions ◽

Digital Light Processing ◽

Fused Deposition ◽

Printing Technique ◽

3D Printed ◽

Semi Solid ◽

Selection Of

Three-dimensional (3D) printing is among the rapidly evolving technologies with applications in many sectors. The pharmaceutical industry is no exception, and the approval of the first 3D-printed tablet (Spiratam®) marked a revolution in the field. Several studies reported the fabrication of different dosage forms using a range of 3D printing techniques. Thermosensitive drugs compose a considerable segment of available medications in the market requiring strict temperature control during processing to ensure their efficacy and safety. Heating involved in some of the 3D printing technologies raises concerns regarding the feasibility of the techniques for printing thermolabile drugs. Studies reported that semi-solid extrusion (SSE) is the commonly used printing technique to fabricate thermosensitive drugs. Digital light processing (DLP), binder jetting (BJ), and stereolithography (SLA) can also be used for the fabrication of thermosensitive drugs as they do not involve heating elements. Nonetheless, degradation of some drugs by light source used in the techniques was reported. Interestingly, fused deposition modelling (FDM) coupled with filling techniques offered protection against thermal degradation. Concepts such as selection of low melting point polymers, adjustment of printing parameters, and coupling of more than one printing technique were exploited in printing thermosensitive drugs. This systematic review presents challenges, 3DP procedures, and future directions of 3D printing of thermo-sensitive formulations.

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3D-Printable PP/SEBS Thermoplastic Elastomeric Blends: Preparation and Properties

Polymers ◽

10.3390/polym11020347 ◽

2019 ◽

Vol 11 (2) ◽

pp. 347 ◽

Cited By ~ 18

Author(s):

Shib Banerjee ◽

Stephen Burbine ◽

Nischay Kodihalli Shivaprakash ◽

Joey Mead

Keyword(s):

3D Printing ◽

Carbon Black ◽

Computer Aided Design ◽

Fused Deposition Modeling ◽

Mechanical Performance ◽

Polymeric Materials ◽

Fused Deposition ◽

3D Printed ◽

Injection Molded ◽

Preferential Location

Currently, material extrusion 3D printing (ME3DP) based on fused deposition modeling (FDM) is considered a highly adaptable and efficient additive manufacturing technique to develop components with complex geometries using computer-aided design. While the 3D printing process for a number of thermoplastic materials using FDM technology has been well demonstrated, there still exists a significant challenge to develop new polymeric materials compatible with ME3DP. The present work reports the development of ME3DP compatible thermoplastic elastomeric (TPE) materials from polypropylene (PP) and styrene-(ethylene-butylene)-styrene (SEBS) block copolymers using a straightforward blending approach, which enables the creation of tailorable materials. Properties of the 3D printed TPEs were compared with traditional injection molded samples. The tensile strength and Young’s modulus of the 3D printed sample were lower than the injection molded samples. However, no significant differences could be found in the melt rheological properties at higher frequency ranges or in the dynamic mechanical behavior. The phase morphologies of the 3D printed and injection molded TPEs were correlated with their respective properties. Reinforcing carbon black was used to increase the mechanical performance of the 3D printed TPE, and the balancing of thermoplastic elastomeric and mechanical properties were achieved at a lower carbon black loading. The preferential location of carbon black in the blend phases was theoretically predicted from wetting parameters. This study was made in order to get an insight to the relationship between morphology and properties of the ME3DP compatible PP/SEBS blends.

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Properties and applications of electrically conductive thermoplastics for additive manufacturing of sensors

tm - Technisches Messen ◽

10.1515/teme-2016-0057 ◽

2017 ◽

Vol 84 (9) ◽

Cited By ~ 6

Author(s):

Benedikt Hampel ◽

Samuel Monshausen ◽

Meinhard Schilling

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Electrical Conductance ◽

Electrically Conductive ◽

Fused Deposition ◽

Printing Technique ◽

Deposition Modeling ◽

3D Printed ◽

3D Printing Technique ◽

Printing Parameters

AbstractIn consequence of the growing diversity of materials in the fused deposition modeling 3D printing technique, electrically conductive materials are commercially available. In this work two filaments based on thermoplastics filled with carbon or metal nanoparticles are analyzed in terms of their electrical conductance. The printing parameters to process the materials with the 3D printer are optimized with the design of experiments (DoE) method. A model to calculate the resistance of such 3D printed structures is presented and a demonstrator as a proof of concept was 3D printed based on these results. In addition, 3D printing of capacitors is investigated.

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3D printers in dentistry: a review of additive manufacturing techniques and materials

Clinical and Laboratorial Research in Dentistry ◽

10.11606/issn.2357-8041.clrd.2021.188502 ◽

2021 ◽

Author(s):

Leonardo Portilha Gomes da Costa ◽

Stephanie Isabel Díaz Zamalloa ◽

Fernando Amorim Mendonça Alves ◽

Renan Spigolon ◽

Leandro Yukio Mano ◽

...

Keyword(s):

Additive Manufacturing ◽

3D Printing ◽

Fused Deposition Modeling ◽

Dental Materials ◽

Clinical Results ◽

Digital Light Processing ◽

Fused Deposition ◽

3D Printers ◽

Manufacturing Techniques ◽

Printed Materials

3D printers manufacture objects used in various dental specialties. Objective: This literature review aims to explore different techniques of current 3D printers and their applications in printed materials for dental purposes. Methods: The online PubMed databases were searched aiming to find applications of different 3D printers in the dental area. The keywords searched were 3D printer, 3D printing, additive manufacturing, rapid prototyping, 3D prototyping, dental materials and dentistry. Results: From the search results, we describe Stereolithography (SLA), Digital Light Processing (DLP), Material Jetting (MJ), Fused Deposition Modeling (FDM), Binder Jetting (BJ) and Dust-based printing techniques. Conclusion: 3D printing enables different additive manufacturing techniques to be used in dentistry, providing better workflows and more satisfying clinical results.

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An overview on 3D Printed Medicine

Material Science Research India ◽

10.13005/msri/180102 ◽

2021 ◽

Vol 18 (1) ◽

pp. 07-13

Author(s):

Neha Thakur ◽

Hari Murthy

Keyword(s):

3D Printing ◽

Fused Deposition Modeling ◽

Low Cost ◽

Selective Laser Sintering ◽

Three Dimensional ◽

Herbal Medicines ◽

Fused Deposition ◽

Digitally Controlled ◽

3D Printed ◽

Semi Solid

Three-dimensional printing (3DP) is a digitally-controlled additive manufacturing technique used for fast prototyping. This paper reviews various 3D printing techniques like Selective Laser Sintering (SLS), Fused Deposition Modeling, (FDM), Semi-solid extrusion (SSE), Stereolithography (SLA), Thermal Inkjet (TIJ) Printing, and Binder jetting 3D Printing along with their application in the field of medicine. Normal medicines are based on the principle of “one-size-fits-all”. This is not true always, it is possible medicine used for curing one patient is giving some side effects to another. To overcome this drawback “3D Printed medicines” are developed. In this paper, 3D printed medicines forming different Active Pharmaceutical Ingredients (API) are reviewed. Printed medicines are capable of only curing the diseases, not for the diagnosis. Nanomedicines have “theranostic” ability which combines therapeutic and diagnostic. Nanoparticles are used as the drug delivery system (DDS) to damaged cells’ specific locations. By the use of nanomedicine, the fast recovery of the disease is possible. The plant-based nanoparticles are used with herbal medicines which give low-cost and less toxic medication called nanobiomedicine. 4D and 5D printing technology for the medical field are also enlightened in this paper.

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Effects of wood flour and MA-EPDM on the properties of fused deposition modeling 3D-printed poly lactic acid composites

BioResources ◽

10.15376/biores.16.4.7122-7138 ◽

2021 ◽

Vol 16 (4) ◽

pp. 7122-7138

Author(s):

Sang-U Bae ◽

Young-Rok Seo ◽

Birm-June Kim ◽

Min Lee

Keyword(s):

Lactic Acid ◽

3D Printing ◽

Fused Deposition Modeling ◽

Wood Flour ◽

Poly Lactic Acid ◽

Common System ◽

Fused Deposition ◽

Deposition Modeling ◽

3D Printed ◽

Material Composite

Fused deposition modeling (FDM) 3D printing technology is the most common system for polymer additive manufacturing (AM). Recent studies have been conducted to expand both the range of materials that can be used for FDM and their applications. As a filler, wood flour was incorporated into poly lactic acid (PLA) polymer to develop a biocomposite material. Composite filaments were manufactured with various wood flour contents and then successfully used for 3D printing. Morphological, mechanical, and biodegradation properties of FDM 3D-printed PLA composites were investigated. To mitigate brittleness, 5 phr of maleic anhydride grafted ethylene propylene diene monomer (MA-EPDM) was added to the composite blends, and microstructural properties of the composites were examined by scanning electron microscopy (SEM). Mechanical strength tests demonstrated that elasticity was imparted to the composites. Additionally, test results showed that the addition of wood flour to the PLA matrix promoted pore generation and further influenced the mechanical and biodegradation properties of the 3D-printed composites. An excellent effect of wood flour on the biodegradation properties of FDM 3D-printed PLA composites was observed.

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COVID-19 and a novel initiative to improve safety by 3D printing personal protective equipment parts from computed tomography

10.21203/rs.3.rs-31671/v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

John Cote ◽

John Haggstrom ◽

Ranuga Vivkanandan ◽

Kristin Ann Coté ◽

Daniel Real ◽

...

Keyword(s):

Computed Tomography ◽

3D Printing ◽

Fused Deposition Modeling ◽

Future Research ◽

Short Supply ◽

Fused Deposition ◽

Electronic Caliper ◽

3D Printed ◽

Original Part ◽

Improved Accuracy

Abstract Background Powered air-purifying respirators are in short supply and can break down with extended use. Replacement parts can become hard to acquire. The aim of this study was to create an innovative quality improvement proof of concept using rapid prototyping. Methods Here we report three cases of 3D printed powered air-purifying respirator parts. 3D printing was performed on all parts using fused deposition modeling with standard polylactic acid, in the same way that presurgical models would be created. Measurements using an electronic caliper as well as CT scans were used to compare an original part to its corresponding 3D printed parts for accuracy. Results Electronic caliper and computed tomography measurements both showed accuracy consistant with current published norms. Conclusions Ultimately, there will be questions surrounding intellectual property, effectiveness and potential long-term safety for these types of 3D printed parts. Future research should look into the addition of specific nanoparticles from the position of cost, efficacy, safety and improved accuracy.

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