7 - 3D printing silk

Three-dimensional (3D) printing is a process for creating 3D objects with various geometries using digital modeling, and it is widely used in the construction and medical industries. In the field of pharmacy, 3D printers were introduced as a suitable manufacturing method in response to the increasing need for “personalization.” Since the first 3D printed drug, Spritam®, was approved by the Food and Drug Administration (FDA) in 2015, 3D printer technology has evolved through considerable research. The 3D printing methods are classified into selective laser sintering, inkjet printing, stereolithography, digital light processing, and fused deposition modeling (FDM) according to the printing method. Among them, FDM, which is a method of extruding filaments through a nozzle, is the most widely used 3D printer method in pharmaceuticals. This review paper covers the detail content of manufacturing drugs by FDM. Owing to its ease of use and relatively low price, many studies have focused on FDM 3D printers. In this review paper, we concretely investigate a series of FDM procedures and parameters and introduce many studies that used FDM 3D printers to control the release, to make novel dosage form, and to deliver the customized doses. FDM is completely different from traditional drug manufacturing methods, and it is expected to achieve personalization. Once mechanical problems and regulatory barriers are overcome and new developments are made, FDM 3D printers will become a unique and effective way to manufacture patient-customized drugs in the pharmaceutical industry.

Three-dimensional printing is a rapidly developing area of technology and manufacturing in the field of oral surgery. The aim of this study was comparison of presurgical models made by two different types of three-dimensional (3D) printing technology. Digital reference models were printed 10 times using fused deposition modelling (FDM) and digital light processing (DLP) techniques. All 3D printed models were scanned using a technical scanner. The trueness, linear measurements, and printing time were evaluated. The diagnostic models were compared with the reference models using linear and mean deviation for trueness measurements with computer software. Paired t-tests were performed to compare the two types of 3D printing technology. A P value < 0.05 was considered statistically significant. For FDM printing, all average distances between the reference points were smaller than the corresponding distances measured on the reference model. For the DLP models, the average distances in the three measurements were smaller than the original. Only one average distance measurement was greater. The mean deviation for trueness was 0.1775 mm for the FDM group and 0.0861 mm for the DLP group. Mean printing time for a single model was 517.6 minutes in FDM technology and 285.3 minutes in DLP. This study confirms that presurgical models manufactured with FDM and DLP technologies are usable in oral surgery. Our findings will facilitate clinical decision-making regarding the best 3D printing technology to use when planning a surgical procedure.

3D printing, also known as Additive manufacturing (AM), has emerged as a transformative technology with applications across various industries, including the medical sector. This review paper provides an overview of the current status of AM technology, its challenges, and its application in the medical industry. The paper covers the different types of AM technologies, such as fused deposition modeling, stereolithography, selective laser sintering, digital light processing, binder jetting, and electron beam melting, and their suitability for medical applications. The most commonly used biomedical materials in AM, such as plastic, metal, ceramic, composite, and bio-inks, are also viewed. The challenges of AM technology, such as material selection, accuracy, precision, regulatory compliance, cost and quality control, and standardization, are also discussed. The review also highlights the various applications of AM in the medical sector, including the production of patient-specific surgical guides, prosthetics, orthotics, and implants. Finally, the review highlights the Internet of Medical Things (IoMT) and artificial intelligence (AI) for regulatory frameworks and safety standards for 3D-printed biomedical devices. The review concludes that AM technology can transform the healthcare industry by enabling patients to access more personalized and reasonably priced treatment alternatives. Despite the challenges, integrating AI and IoMT with 3D printing technology is expected to play a vital role in the future of biomedical device applications, leading to further advancements and improvements in patient care. More research is needed to address the challenges and optimize its use for medical applications to utilize AM's potential in the medical industry fully.

The purpose of this paper is to make an analysis of the advanced technologies for 3D printing of pharmaceutical products for personalised medicine.A review of the basic 3D printing methods used in pharmaceutical technologies is conducted. The main types of printed solid dosage forms are examined, along with the primary advantages and disadvantages of 3D printing compared to conventional drug production. Each method is evaluated in terms of working principles, material compatibility, advantages, and limitations.Revealed that stereolithography (SLA), selective laser sintering (SLS), fused deposition modelling (FDM), ink-jet printing (IJP), and semi-solid extrusion (SSE) are the most suitable 3D printing processes for producing pharmaceutical products. The combination of two methods ensures better results, as illustrated by examples of the main types of printed solid dosage forms.The 3D printing technologies for production of pharmaceutical products present several limitations such as: uneven geometries and porous structures, necessitating the fabrication of larger and irregular dosage forms to ensure the required drug load for the patient; degradation of thermolabile drugs during FDM process; increased hardness of FDM produced tablets impairing drug release.The advanced 3D printing technologies offer the ability to produce new formulations easily through simple design modifications in software, compared to conventional manufacturing. They enable the design of flexible formulations with complex release profiles and the personalised production of dosage forms tailored to individual patients.3D printing has emerged as a transformative technology in pharmaceutical manufacturing, enabling the production of personalised dosage forms with precise drug loading, tailored release profiles, and complex geometries. The review not only summarises the main applicable techniques but also highlights the most recommended methods for personalised pharmacotherapy. The versatility and adaptability of 3D printing provide promising solutions for personalised therapy, emergency drug manufacturing, and enhanced patient compliance, marking a significant step toward decentralised, digital pharmaceutical production.

14 - Medical additive manufacturing then, now, and will

Recent developments in three-dimensional (3D) printing technology offer immense potential in fabricating scaffolds and implants for various biomedical applications, especially for bone repair and regeneration. As the availability of autologous bone sources and commercial products is limited and surgical methods do not help in complete regeneration, it is necessary to develop alternative approaches for repairing large segmental bone defects. The 3D printing technology can effectively integrate different types of living cells within a 3D construct made up of conventional micro- or nanoscale biomaterials to create an artificial bone graft capable of regenerating the damaged tissues. This article reviews the developments and applications of 3D printing in bone tissue engineering and highlights the numerous conventional biomaterials and nanomaterials that have been used in the production of 3D-printed scaffolds. A comprehensive overview of the 3D printing methods such as stereolithography (SLA), selective laser sintering (SLS), fused deposition modeling (FDM), and ink-jet 3D printing, and their technical and clinical applications in bone repair and regeneration has been provided. The review is expected to be useful for readers to gain an insight into the state-of-the-art of 3D printing of bone substitutes and their translational perspectives.

Scaffolds for tissue engineering and drug delivery application have made significant progress since the first engineered scaffolds were developed more than 20 years ago. Scaffolds are used for reconstructive and regenerative applications of both soft and hard tissues. Materials used for scaffold range from biodegradable polymers, bioactive ceramics, amorphous and glass ceramics, and combinations of the polymers and ceramics. The mechanism of bioactive ceramics and glass ceramics is reviewed with special attention on the combinatorial effect of ion release on gene expression and mineralization process. The scaffolds developed should have an open architecture to promote vascularization while retaining the structural integrity during the integration to surrounding tissue. Latest developments in scaffold production including transfer printing replication, stereolithography, selective laser sintering, fused deposition modeling, 3D printing, robocasting, two photon polymerization, and inkjet printing are reviewed.

This study addresses the challenge of designing a high-induction air diffuser with a complex geometry that effectively mixes and entrains more ambient air, raising concerns about potential noise increase. The research focuses on the acoustic performance of innovative 3D-printed air diffusers compared to the original air diffuser installed in the Dacia-Renault Duster vehicle. The four 3D-printed air diffusers, created using FDM (Fused Deposition Modelling), SLS (Selective Laser Sintering), DLP (Digital Light Processing), and SLA (Stereolithography), were tested to evaluate a single configuration due to concerns that the surface quality resulting from 3D printing could increase the noise produced by these diffusers. Using a professional sound level meter, acoustic measurements were conducted at the V2 (23.9 m3/h) and V3 (33.6 m3/h) flow rate settings. Results showed that the traditional air diffuser had the highest noise levels, measuring 38.2 dB at V2 and 39.6 dB at V3, which were 7.33% and 8.84% louder, respectively, than the innovative designs. Despite the DLP-printed diffuser being the quietest on V2 speed setting, the SLA-printed variant was preferred due to its superior dimensional tolerances and because the differences in noise were small.

This study evaluates the accuracy of drill guides fabricated in medical-grade, biocompatible materials for static, computer-aided implant surgery (sCAIS). The virtually planned drill guides of ten completed patient cases were printed (n = 40) using professional (Material Jetting (MJ)) and consumer-level three-dimensional (3D) printing technologies, namely, Stereolithography (SLA), Fused Filament Fabrication (FFF), and Digital Light Processing (DLP). After printing and post-processing, the drill guides were digitized using an optical scanner. Subsequently, the drill guide’s original (reference) data and the surface scans of the digitized 3D-printed drill guide were superimposed to evaluate their incongruencies. The accuracy of the 3D-printed drill guides was calculated by determining the root mean square (RMS) values. Additionally, cast models of the planned cases were used to check that the drill guides fitted manually. The RMS (mean ± SD) values for the accuracy of 3D-printed drill guides were—MJ (0.09 ± 0.01 mm), SLA (0.12 ± 0.02 mm), FFF (0.18 ± 0.04 mm), and DLP (0.25 ± 0.05 mm). Upon a subjective assessment, all drill guides could be mounted on the cast models without hindrance. The results revealed statistically significant differences (p < 0.01) in all except the MJ- and SLA-printed drill guides. Although the measured differences in accuracy were statistically significant, the deviations were negligible from a clinical point of view. Within the limits of this study, we conclude that consumer-level 3D printers can produce surgical guides with a similar accuracy to a high-end, professional 3D printer with reduced costs.

Chapter 2 - 3D printing and nanotechnology

Three-dimensional (3D) printing is an emerging and enabling technology that is paving its way in different fields of research, including analytical science, for the fabrication of custom devices and portable sensing platforms based on additive manufacturing of objects from Computer-Aided Design (CAD) models. In fact, the last five years have witnessed tremendous advances in novel materials and composites with improved chemical properties (e.g., noble metals, carbon nanomaterials, and chemically resistant polymers). Printing platforms for fabrication of low-cost devices have capitalized on stereolithography (SLA) or dynamic light processing (DLP), inkjet printing, fused deposition modelling (FDM), and selective laser sintering (SLS) that enable decentralized (in situ) measurements. The main advantage of 3D printing is the capability of rapid and single-step prototyping of holders, scaffolds, and integrated complex systems with geometries that cannot easily be manufactured by conventional means, such as computer numerical controlled milling and soft-lithographic approaches. Furthermore, the outreach of this technique has been expanded by the lowering costs of the machinery, the user-friendliness of the CAD software and especially the commercial strategies addressed to the nontechnical and nonscientific collective, currently called the 'maker community'.

Abstract. This paper describes the Charter on the preservation of the digital heritage and it also presents the five main printing technologies, FDM (Fused Deposition Modeling), SLA (Stereo Lithography Apparatus), DLP (Digital Light Processing), LCD (Liquid Crystal Display) and SLS (selective laser sintering) technology. Besides, It presents a methodology to process the restoration of a porcelain bowl through three-dimensional scanning and FDM (Fused Deposition Modeling) and LCD (Liquid Crystal Display) 3D printing technologies. First, the porcelain bowl is scanned with the scanner. Then the modeling software is used to reconstruct the missing part that the bowl presents. Finally, the reconstructed 3D fragment model is printed, completed and chromatically reintegrated. In order to optimize this restoration method to achieve the best visual effect similar to the appearance of the porcelain bowl, different printing materials are used for testing. This type of restoration method can improve the final appearance of the intervened area, minimize the operation of the object and can also make it be shaped quickly and precisely.

Recently, three‐dimensional (3D) printing has become a research focus point and has evolved as a powerful tool for manufacturing complex objects for advanced technology platform designs. Herein, we review the current state‐of‐the‐art 3D‐printed hydrogels and aerogels for wastewater treatment and energy storage applications. Several 3D printing methods such as direct ink writing, digital light processing, and fused filament fabrication have been discussed. Among these, direct ink writing is the most employed 3D printing technique for hydrogels and aerogels. We systematically investigated the most important results of several 3D‐printed hydrogels and aerogels for adsorption, photocatalysis, membrane filtration, and desalination for wastewater treatment, supercapacitors, and batteries in energy storage applications. Finally, we conclude our understanding with the prospect of future opportunities in this field using 3D‐printed hydrogels and aerogels for wastewater treatment and energy storage applications. In summary, the fundamental knowledge of 3D printing and critical assessment of the key literature on 3D‐printed hydrogels and aerogels and their applications in water treatment and energy storage will provide guidance for future studies in smart materials and waste management aspects of sustainability.

Emergency and disaster medical care often face resource or equipment shortages. 3D printing technology has been proven to be effective in cases with insufficient supply chains. MAYO tubes and stethoscopes are essential components of ABCDE patient examinations; however, 3D-printed variants have not been fully tested. These 3D-printed instruments were substituted and validated in a simulated pre-hospital environment.In total, 26 participants were included in this study. Fifteen clinicians or paramedics with at least 3 years of professional experience and 10 medical students. One student was excluded because he had relevant experience with emergency care. As basic tasks, the placement of MAYO tubes and auscultation with stethoscopes were performed using medical simulators. 3D printed instruments were compared with conventional clinical devices by measuring the time required for the intervention, success rate, and user satisfaction. In the study FFF (Fused Filament Fabrication (FFF), SLS (Selective Laser Sintering (SLS), and SLA (stereolithography) 3D printing were used in this study.The times required for implementation and auscultation were examined for each instrument. There was no significant difference between the MAYO tube (p = 0.798) and the stethoscope (p = 0.676). In the case of stethoscopy, the study investigated the correct diagnosis, and no significant difference was found (p = 0.239), although an interesting trend was observed. Regarding the MAYO tube, the study found no significant difference in correct position formation (p = 0.163). The experience levels of the groups did not influence these factors. However, significant differences in user satisfaction were found in both cases in favour of the conventional versions (p < 0.001).Overall, the results of this study suggest that 3D-printed devices could be suitable replacements for clinic-based devices in emergency situations. The 3D-printed devices did not perform inferiorly at any of the indicated points compared to their classical counterparts. However, the practical applicability of the devices used in this study requires further investigation.

ObjectiveThe aim of the study is to develop a workflow to establish geometrical quality criteria for 3D printed anatomical models as a guidance for selecting the most suitable 3D printing technologies available in a clinical environment. MethodsWe defined the 3D geometry of a 25-year-old male patient’s L4 vertebra and the geometry was then printed using two technologies, which differ in printing resolution and affordability: Fused Deposition Modelling (FDM) and Digital Light Processing (DLP). In order to measure geometrical accuracy, the 3D scans of two physical models were compared to the virtual input model. To compare surface qualities of these printing technologies we determined surface roughness for two regions of interest. Finally, we present our experience in the clinical application of a physical model in a congenital deformity case. ResultsThe analysis of the distribution of the modified Hausdorff distance values along the vertebral surface meshes (99% of values <1 mm) of the 3D printed models provides evidence for high printing accuracy in both printing techniques. Our results demonstrate that the surface qualities, measured by roughness are adequate (~99% of values <0.1 mm) for both physical models. Finally, we implemented the FDM physical model for surgical planning. ConclusionWe present a workflow capable of determining the quality of 3D printed models and the application of a high quality and affordable 3D printed spine physical model in the pre operative planning. As a result of the visual guidance provided by the physical model, we were able to define the optimal trajectory of the screw insertion during surgery.