Bone model studies for DMLS based 3D printed innovative dental implant

Two types of additive manufacturing (AM) techniques, fused filament fabrication (FFF) and selective laser sintering (SLS), were employed to fabricate specimens from three widely used AM polymers: polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), and polyamide (PA): the first two using FFF and PA using SLS. The single‐edge notch bending (SENB) test was employed to measure the mode‐I fracture toughnesses of bulk and AM specimens in three directions relative to the printing direction. Unlike their bulk counterparts, AM polymers exhibited anisotropic fracture toughness. The degree of anisotropy in FFF‐PLA was much larger than FFF‐ABS and SLS‐PA. The smallest fracture toughness value for each AM polymer was achieved along the transverse printing direction. Different AM techniques affect fracture toughness differently. For instance, FFF is shown to increase PLA's plastic deformation, while SLS reduces PA's ductility. The decrease in fracture toughness is consistently observed when transitioning from bulk polymers to AM ones, reaching as much as 75%. This study provides insights into the fracture toughness of AM parts made via popular plastics, which are crucial for designing structural parts using FFF and SLS processes.

Interest in three-dimensional (3D) printing processes has grown significantly, and several types have been developed. These 3D printing processes are classified as Selective Laser Sintering (SLS), Stereo-Lithography Apparatus (SLA), and Fused Deposition Modeling (FDM). SLS can be applied to many materials, but because it uses a laser-based material removal process, it is expensive. SLA enables fast and precise manufacturing, but available materials are limited. FDM printing’s benefits are its reasonable price and easy accessibility. However, metal printing using FDM can involve technical problems, such as suitable component supply or the thermal expansion of the heating part. Thus, FDM printing primarily uses materials with low melting points, such as acrylonitrile butadiene styrene (ABS) or polylactic acid (PLA) resin. In this study, an FDM process for enabling metal printing is suggested. Particularly, the nozzle and heatsink for this process are focused for stable printing. To design the nozzle and heatsink, multi-physical phenomena, including thermal expansion and heat transfer, had to be considered. Therefore, COMSOL Multiphysics, an FEM analysis program, was used to analyze the maximum temperature, thermal expansion, and principal stress. Finally, its performance was confirmed through an experiment.KeyWords : 3-Dimensional Printing(3 ), Fused Deposition Modeling(차원 인쇄 압출 적층 방식), Aluminum( ), Multiphysical Analysis(알루미늄 다물리 해석)

Fuse Deposition Modeling (FDM) offer several advantages such as less expensive material, lack of expensive lasers and allows complex geometry to be built. However, FDM have limitations such as seam lines appear between layers and excess material residue, leading to surface roughness and poor finish. Ultrasound has been applied in various conventional machining process and shows good machined surface finish. However, from the literature review, it was found there is no investigation made on the application of ultrasound for Additive Manufacturing (AM) especially for FDM. This paper presents an adaptive approach to improve surface finish of FDM sample by applying ultrasonic vibration. The papers discuss the result of the surface finish of test piece printed via a desktop FDM system whereby an ultrasound device that was securely mounted onto the platform during printing process. Frequency that was used in the experiment is 11, 16 and 21 kHz with acrylonitrile butadiene styrene (ABS) material. Optical microscope with the aid of pro VIS software version 2.90 was used to measure the surface roughness of the four samples printed with a vibration in the above specified frequency. It was found that a 21 kHz frequency applied to the FDM process achieved the best surface finish due to less surface defects found and thickness had finer layers being produced. The results from this study could potentially be applied to other AM system such as the selective laser sintering, electron beam machining and stereolithography. The new data on effects of ultrasonic FDM technique and machining parameter for achieving improved surface finish has potential benefit to be used in various industries such as automotive, consumer, medical, sports, etc to produce prototypes or customized end used product or part. The data will benefit in term of product design and development elimination of manual post processing. Further study that could be done is to use different types of material such as polyactic acid (PLA) or composite material.

Comparison of energy consumption of ABS and PLA while 3 D printing with fused deposition modeling process

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.

The implementation of three-dimensional printing technology has revolutionised dentistry over the past decade. The desired object is scanned by a 3D scanner or built using computer-aided design (CAD)/computer-aided manufacturing (CAM) software. CAD designs of dental implants can be analysed by the finite element method (FEM). Finite element analysis (FEA) is done by discretising the geometrically developed model into smaller and simpler elements and analysing the 3D model using different boundary conditions on different nodes. Depending on the materials of choice, various printing methods are available, such as selective laser sintering (SLS), stereolithography, fused deposition modelling, and laminated object manufacturing. Dental implants are designed with the help of different biomaterials, such as polymers, metals, and ceramics. Clinicians should know the latest implant materials for successful implant therapy. This review article investigates 3D printing on various dental implants, designs, simulations, and limitations. The last part of the article discusses different properties of the implant materials used in the designs.

Chapter 2 - 3D printing and nanotechnology

Performance Prediction and Experimental Validation of 3D Printed Dental Titanium Ti64ELI Implant

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.

Significant advances in fused deposition modeling (FDM), as well as its myriad applications, have led to its growing prominence among additive manufacturing (AM) technologies. When the technology was first developed, it was used for rapid prototyping to examine and analyze a product in the design stage. FDM facilitates rapid production, requires inexpensive tools, and can fabricate complex-shaped parts; it, therefore, became popular and its use widespread. However, various FDM processing parameters have proven to affect the printed part’s mechanical properties to different extents. The values for the printing process parameters are carefully selected based on the part’s application. This study investigates the effects of four process parameters (raster angle, layer thickness, infill percentage, and printing speed) on the mechanical behavior of printed parts that are based on available literature data. These process parameter’s influence on part’s mechanical properties varies depending on the FDM material. The study focuses on four FDM materials: polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), polyether ether ketone (PEEK), and polyethylene terephthalate glycol (PETG). This paper summarizes the state-of-the-art literature to show how sensitive the material’s mechanical properties are to each process parameter. The effect of each parameter on each material was quantified and ranked using analysis of variance (ANOVA). The results show that infill percentage then layer thickness are the most influential process parameter on most of the material’s mechanical properties. In addition, this work identifies gaps in existing studies and highlights opportunities for future research.

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.

Fused deposition modeling (FDM) is highly commercialized Rapid Prototyping (RP) technology for its ability to build complex parts with low cost in a short period of time. The process parameters in the FDM play a vital role in the mechanical properties of the polymeric parts. Most of the research studies show that the variable parameters such as orientation, layer thickness, raster angle, raster width, and air gap are some of the key parameters that affect the mechanical properties of FDM-processed polymeric parts. However, no reports have been made regarding the influence of nozzle diameter with raster width on the tensile properties of FDM fabricated polymeric parts. This work was devoted to achieving improved and isotropic mechanical properties in polycarbonate (PC) and PC/carbon nanotube (PC/CNT) nanocomposites by investigating the effect of printing parameters in FDM process. The nozzle diameter to raster width ratio, α was found to significantly affect the mechanical properties. The printing direction dependency in tensile properties were studied with the ratio α &lt; 1 and α≥ 1 at three different raster angles of 0°, 45°/−45° and 90°. For α &lt; 1, Ultimate tensile strength and modulus of elasticity were higher for 0°, compared to 45°/−45° and 90° raster angles. However, for α ≥ 1, the ultimate tensile strength and the modulus of elasticity showed little dependency to print direction. This certainly determines the decrease in anisotropy at higher values of α. Mesostructure characterization with microscopy and image analysis were used to further explain the printing behavior and the resultant properties of the printed samples.

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.

Additive manufacturing (AM) technologies can enable the direct fabrication of customized physical objects with complex shapes, based on computer-aided design models. This technology is changing the digital manufacturing industry and has become a subject of considerable interest in digital implant dentistry. Personalized dentistry implant treatments for individual patients can be achieved through Additive manufacturing. Herein, we review the applications of Additive manufacturing technologies in oral implantology, including implant surgery, and implant and restoration products, such as surgical guides for implantation, custom titanium meshes for bone augmentation, personalized or non-personalized dental implants, custom trays, implant casts, and implant-support frameworks, among others. In addition, this review also focuses on Additive manufacturing technologies commonly used in oral implantology. Stereolithography, digital light processing, and fused deposition modeling are often used to construct surgical guides and implant casts, whereas direct metal laser sintering, selective laser melting, and electron beam melting can be applied to fabricate dental implants, personalized titanium meshes, and denture frameworks. Moreover, it is sometimes required to combine Additive manufacturing technology with milling and other cutting and finishing techniques to ensure that the product is suitable for its final application.

Not much time has passed since the appearance of the first 3D printer. Today there are many different printers. They differ in various 3D printing technologies, namely: Stereolithography – SL, Selective Laser Sintering, Fused Deposition Modeling – FDM, Laminated Object Manufacturing – LOM, Polyjet and Ployjet Matrix. In recent years, the spread of 3D printing technology has become and continues to be used more and more today. Of course, in the future we will see a large-scale spread of additive methods, but the practical application of 3D printing today is available to everyone. Melting deposition modeling technologies have become widespread and available. The authors in this article consider possible options for upgrading the mounting of the end sensor of the Z Axis and automating the process of calibration of the zero gap of the extruder nozzle relative to the working surface of the printer. This calibration is important. This affects the accuracy and printing process of the future plastic model. During the operation of the 3D printer, it is often necessary to service the extruder, which forces the process of calibrating the zero gap of the printer nozzle. Optimally correct selected nozzle clearance affects the accuracy, geometry of the model and printing as a whole. It also allows you to get rid of peeling off the model from the desktop surface and the destruction of the model during printing.