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Item3D Printed ABS and Carbon Fiber Reinforced Polymer Specimens for Engineering Education(Springer, 2016) Golub, Michael; Guo, Xingye; Jung, Mingyo; Zhang, Jing; Department of Mechanical Engineering, School of Engineering and TechnologyThree 3D printed plastic materials, ABS, ABS plus, and CFRP, have been studied for their potential applications in engineering education. Using tensile test, the stress strain curves of the materials have been measured. The Young’s modulus, ultimate strength, and fracture toughness of the materials are calculated from the stress strain curve. The results show that CFRP has the highest stiffness or Young’s modulus. ABS plus has strongest mechanical properties, with highest ultimate strength and fracture toughness. With the measured properties, the 3D printed samples are a viable solution for engineering students to learn mechanical properties of materials. Item3D printing in surgical simulation: emphasized importance in the COVID-19 pandemic era(Future Medicine, 2021-03-01) Michaels, Ross; Witsberger, Chelsey A; Powell, Allison R; Koka, Krishna; Cohen, Katheryn; Nourmohammadi, Zahra; Green, Glen E; Zopf, David A; Otolaryngology -- Head and Neck Surgery, School of MedicineHistorically, surgical training was an apprenticeship model of see one, do one, teach one. However, a proficiency-based training approach has become increasingly implemented for assessing surgical skills with performance scores used as benchmarks to track trainee proficiency . Surgical simulators are starting to be utilized more to assess proficiency in trainees on certain procedures with many residency programs having simulation as a piece of their training curriculum. Today, simulation in surgical training takes many forms. Live animals and cadavers are often implemented since these simulators can simulate operating on realistic tissue and on human anatomy respectively. There are also basic simulators that are models that simulate a component of an operation such as suturing or knot-tying. These help trainees practice certain surgical skills necessary for completing a procedure. Some of these simulators have become more complex and simulate several steps or even an entire procedure such as joint replacements and fixating fractures . With the increased availability in 3D printing technology and a push toward personalized medicine, 3D printing research has exponentially increased in recent years and has been an area of investigation for the development of surgical simulators . Using a 3D printer to construct models for simulation leads to vast opportunity to customize the simulator while significantly reducing cost. Prior to the advent of 3D printing and additive manufacturing, computed tomography (CT) data were used to construct anatomic models using subtractive manufacturing with the first model made in 1979 . Commercial 3D printers became available in the 1980s and were introduced into the medical field in 1994 . Currently, 3D printing has several surgical applications including anatomic models for surgical planning, simulation and education; implants and prostheses; and surgical guides . Item3D Printing Law(2016) Hook, Sara AnneWhoever you represent in relation to 3D printing, you need to ensure that you're in-the-know regarding the latest rules and regulations. In this fast paced legal program, you'll maximize insight and gain cutting-edge pointers for advising your clients on this new area of law. Dig deep into the science, technology, rules and requirements regulating 3D printing today - AND identify key business, legal, and technical issues that will oversee this evolving landscape now, and in the near future. Review 3D printing laws and get the latest legislative updates, rules and regulations. Identify top liability traps, legal landmines and mistakes. Review intellectual property rights and issues. Analyze 3D printing taxation considerations. ItemA Highly Ordered, Nanostructured Fluorinated CaP-Coated Melt Electrowritten Scaffold for Periodontal Tissue Regeneration(Wiley, 2021) Daghrery, Arwa; Ferreira, Jessica A.; de Souza Araújo, Isaac J.; Clarkson, Brian H.; Eckert, George J.; Bhaduri, Sarit B.; Malda, Jos; Bottino, Marco C.; Biostatistics, School of Public HealthPeriodontitis is a chronic inflammatory, bacteria-triggered disorder affecting nearly half of American adults. Although some level of tissue regeneration is realized, its low success in complex cases demands superior strategies to amplify regenerative capacity. Herein, highly ordered scaffolds are engineered via Melt ElectroWriting (MEW), and the effects of strand spacing, as well as the presence of a nanostructured fluorinated calcium phosphate (F/CaP) coating on the adhesion/proliferation, and osteogenic differentiation of human-derived periodontal ligament stem cells, are investigated. Upon initial cell-scaffold interaction screening aimed at defining the most suitable design, MEW poly(𝝐-caprolactone) scaffolds with 500 µm strand spacing are chosen. Following an alkali treatment, scaffolds are immersed in a pre-established solution to allow for coating formation. The presence of a nanostructured F/CaP coating leads to a marked upregulation of osteogenic genes and attenuated bacterial growth. In vivo findings confirm that the F/CaP-coated scaffolds are biocompatible and lead to periodontal regeneration when implanted in a rat mandibular periodontal fenestration defect model. In aggregate, it is considered that this work can contribute to the development of personalized scaffolds capable of enabling tissue-specific differentiation of progenitor cells, and thus guide simultaneous and coordinated regeneration of soft and hard periodontal tissues, while providing antimicrobial protection. ItemA novel decellularized matrix of Wnt signaling-activated osteocytes accelerates the repair of critical-sized parietal bone defects with osteoclastogenesis, angiogenesis, and neurogenesis(Elsevier, 2022-08-16) Wang, Xiaofang; Ma, Yufei; Chen, Jie; Liu, Yujiao; Liu, Guangliang; Wang, Pengtao; Wang, Bo; Taketo, Makoto M.; Bellido, Teresita; Tu, Xiaolin; Anatomy, Cell Biology and Physiology, School of MedicineCell source is the key to decellularized matrix (DM) strategy. This study compared 3 cell types, osteocytes with/without dominant active Wnt/β-catenin signaling (daCO and WTO) and bone marrow stromal cells (BMSCs) for their DMs in bone repair. Decellularization removes all organelles and >95% DNA, and retained >74% collagen and >71% GAG, maintains the integrity of cell basement membrane with dense boundaries showing oval and honeycomb structure in osteocytic DM and smooth but irregular shape in the BMSC-DM. DM produced higher cell survival rate (90%) and higher proliferative activity. In vitro, daCO-DM induces more and longer stress fibers in BMSCs, conducive to cell adhesion, spreading, and osteogenic differentiation. 8-wk after implantation of the critical-sized parietal bone defect model, daCO-DM formed tight structures, composed of a large number of densely-arranged type-I collagen under polarized light microscope, which is similar to and integrated with host bone. BV/TV (>54%) was 1.5, 2.9, and 3.5 times of WTO-DM, BMSC-DM, and none-DM groups, and N.Ob/T.Ar (3.2 × 102/mm2) was 1.7, 2.9, and 3.3 times. At 4-wk, daCO-DM induced osteoclastogenesis, 2.3 times higher than WTO-DM; but BMSC-DM or none-DM didn't. daCO-DM increased the expression of RANKL and MCSF, Vegfa and Angpt1, and Ngf in BMSCs, which contributes to osteoclastogenesis, angiogenesis, and neurogenesis, respectively. daCO-DM promoted H-type vessel formation and nerve markers β3-tubulin and NeuN expression. Conclusion: daCO-DM produces metabolic and neurovascularized organoid bone to accelerate the repair of bone defects. These features are expected to achieve the effect of autologous bone transplantation, suitable for transformation application. ItemAdvanced Scaffolds for Dental Pulp and Periodontal Regeneration(Elsevier, 2017-10) Bottino, Marco C.; Pankajakshan, Divya; Nör, Jacques E.; Biomedical Sciences and Comprehensive Care, School of DentistryNo current therapy promotes root canal disinfection and regeneration of the pulp-dentin complex in cases of pulp necrosis. Antibiotic pastes used to eradicate canal infection negatively affect stem cell survival. Three-dimensional easy-to-fit antibiotic-eluting nanofibers, combined with injectable scaffolds, enriched or not with stem cells and/or growth factors, may increase the likelihood of achieving predictable dental pulp regeneration. Periodontitis is an aggressive disease that impairs the integrity of tooth-supporting structures and may lead to tooth loss. The latest advances in membrane biomodification to endow needed functionalities and technologies to engineer patient-specific membranes/constructs to amplify periodontal regeneration are presented. ItemCAD-CAM Hollow Obturator Prosthesis: A Technical Report(Wiley, 2022) Alfaraj, Amal; Su, Fang-Yu; Lin, Wei-Shao; Prosthodontics, School of DentistryAn obturator with a hollow bulb can decrease the overall weight of the prosthesis, stress on the underlying tissues, and patient discomfort. Although many techniques and materials have been proposed in the literature for hollowing the obturator prosthesis, they are often time-consuming and technique sensitive. This proposed technique used an open-source software program to hollow digital design of solid obturator base from a commercially available software in one single convenient step. The hollowing process allowed precise control of prosthesis thickness at the hollow space area for desirable hermetic seal and prosthesis strength. ItemCharacterization of tensile and hardness properties and microstructure of 3D printed bronze metal clay(2017) Golub, Michael; Zhang, JingBronze is a popular metal for many important uses. Currently, there are no economical 3D printers that can print Bronze powders. A recent product, Bronze Metal Clay (BMC) has arrived. Additionally, commercial metal 3D printers require laser or electron beam sources, which are expensive and not easily accessible. The objective of this research is to develop a new two-step processing technique to produce 3D printed metallic component. The processing step includes room temperature 3D printing followed by high-temperature sintering. Since no material data exists for this clay, the tensile strength and hardness properties of BMC are compared to wrought counterpart. In this research tests are completed to determine the mechanical properties of Cu89Sn11 Bronze Metal Clay. The author of this thesis compares the physical properties of the same material in two different formats: 3D printed clay and molded clay. Using measured stress-strain curves and derived mechanical properties, including Young's modulus, yield strength, and ultimate tensile strength, the two formats demonstrate inherit differences. The Ultimate tensile strength for molded BMC and 3D-printed specimens sintered at 960 C was 161.94 MPa and 157 MPa, respectively. A 3D printed specimen which was red at 843 C had 104.32 MPa tensile strength. Factory acquired C90700 specimen had an ultimate stress of 209.29 MPa. The Young's modulus for molded BMC and 3D-printed specimens sintered at 960 C was 36.41 GPa and 37.05 GPa, respectively. The 843 C 3D-printed specimen had a modulus of 22.12 GPa. C90700 had the highest modulus of 76.81 GPa. The Yield stress values for molded BMC and 3D-printed specimens sintered at 960 C was 77.81 MPa and 72.82 MPa, respectively. The 3D-printed specimen had 46.44 MPa. C90700 specimen had 115.21 MPa. Hand molded specimens had a Rockwell hardness HRB85, while printed samples had a mean of HRB69. Also, molded samples recorded a higher Young's Modulus of 43 GPa vs. 33 GPa for the printed specimens. Both samples were weaker than the wrought Cu88:8Sn11P0:2 which had a 72 GPa. Cu88:8Sn11P0:2 also was a harder material with an HRC45. The property di erence between 3D printed, molded, and wrought samples was explained by examining their micro structures. It shows that 3D printed sample had more pores than the molded one due to printing process. This study demonstrates the flexibility and feasibility of using 3D printing to produce metallic components, without laser or electron beam source. ItemCharacterization of tensile, creep, and fatigue properties of 3D printed Acrylonitrile Butadiene Styrene(2016-08) Zhang, Hanyin; Zhang, Jing; Ryu, Jong Eun; Jones, Alan S.; Anwar, SohelAcrylonitrile Butadiene Styrene (ABS) is the most widely used thermoplastics in 3D printing for making models, prototypes, patterns, tools and end-use parts. However, there is a lack of systematic understanding of the mechanical properties of 3D printed ABS components, including orientation-dependent tensile strength, creep, and fatigue properties. These mechanical properties are critically needed for design and application of 3D printed components. The main objective of this research is to systematically characterize key mechanical properties of 3D printed ABS components, including tensile, creep, and fatigue properties. Additionally, the eff ects of printing orientation on the mechanical prop- erties are investigated. There are two research approaches employed in the thesis: rst, experimental investigation of the tensile, creep, and fatigue properties of the 3D printed ABS components; second, laminate based finite-element modeling of tensile test to understand the stress distributions in different printing layers. The major conclusions of the thesis work are summarized as follows. The tensile test experiments show that the 0 printing orientation has the highest Young's modulus, 1.81 GPa, and ultimate strength, 224 MPa. The tensile test simulation shows a similar Young's modulus as the experiment in elastic region, indicating the robustness of laminate based finite element model. In the creep test, the 90 printing orientation has the lowest k value of 0.2 in the plastics creep model, suggesting the 90 is the most creep resistant among 0 , 45 , and 90 printing orientations. In the fatigue test, the average cycle number under load of 30 N is 3796 revolutions. The average cycle number decreases to 128 revolutions when the load is below 60N. Using the Paris Law, with the crack size of 0.75 mm long and stress intensity factor is varied from 352 to 700 MN -m^3/2 , the predicted fatigue crack growth rate is 0.0341 mm/cycle.