Application Of 3D Printing Research Articles

PO0702: Custom 3D-Printed Surface Brachytherapy Applicators for Skin Cancer Treatment, Trends Seen by Vendor

PO0702: Custom 3D-Printed Surface Brachytherapy Applicators for Skin Cancer Treatment, Trends Seen by Vendor

Skin Posters PO0701: A Novel 3D-Printed Surface Applicator for Treating Merkel Cell Carcinoma of the Hand with High Dose Rate Brachytherapy

Skin Posters PO0701: A Novel 3D-Printed Surface Applicator for Treating Merkel Cell Carcinoma of the Hand with High Dose Rate Brachytherapy

Suitability of UR5 Robot for Robotic 3D Printing

The present paper describes the measurement of the drift of unidirectional pose accuracy, repeatability, and static compliance of a collaborative robot employing a measurement methodology that relies on the description of a virtual ISO cube placed in the robot’s workspace. The measurements aimed to investigate and assess the suitability of the UR5 six-axis collaborative robot for its application in robotic 3D printing. An experimental laboratory measurement workstation was constructed to perform the measurements, and control measurements were performed. The measurements involved describing the TCP point of the robot tool at five measurement points located in a virtual ISO cube during a minimum of 30 repeated measurement cycles. A camera and six linear incremental sensors with assessment units were used for the measurements. The measurements were performed in compliance with the regulations of STN ISO 9283 standard for this type of measurement. As a result of the measurements, the technical specifications of the drift and static compliance of the controlled robotic arm were verified, and the results were compared with the values specified by the manufacturer. Following the measurements and assessment of the results, it was possible to assess the suitability of the used UR5 robotic arm for its application in robotic 3D printing and to propose possible recommendations for the calibration of the robot and the process settings of the printing system for the production of objects using FDM technology.

A review on layerless 3D printing: challenges and applications

Purpose This paper aims to provide a full introduction, new classification, comparison and investigation of the challenges as well as applications of layerless 3D printing, which is one of the industry 4.0 pioneers. Design/methodology/approach Given the significance and novelty of uniform 3D printing, more than 250 publications were collected and reviewed in an unbiased and clear manner. Findings As a result, the majority of uniform parts printed in polymer form are known up to this point. In a novel division for better researchers’ comprehension, uniform printing systems were classified into three categories: oxygen inhibition (OI), liquid lubrication (LL) and photon penetration (PP), and each was thoroughly investigated. Furthermore, these three approaches were evaluated in terms of printing speed, precision and accuracy, manufacturing scale and cost. Originality/value The parameters of each approach were compared independently, and then a practical comparison was conducted among these three approaches. Finally, a variety of technologies, opportunities, challenges and advantages of each significant method, as well as a future outlook for layerless rapid prototyping, are presented.

Application of electrospinning and 3D-printing based bilayer composite scaffold in the skull base reconstruction during transnasal surgery

Skull base defects are a common complication after transsphenoidal endoscopic surgery, and their commonly used autologous tissue repair has limited clinical outcomes. Tissue-engineered scaffolds prepared by advanced techniques of electrostatic spinning and three-dimensional (3D) printing was an effective way to solve this problem. In this study, soft tissue scaffolds consisting of centripetal nanofiber mats and 3D-printed hard tissue scaffolds consisting of porous structures were prepared, respectively. And the two layers were combined to obtain bilayer composite scaffolds. The physicochemical characterization proved that the nanofiber mat prepared by polylactide-polycaprolactone (PLCL) electrospinning had a uniform centripetal nanofiber structure, and the loaded bFGF growth factor could achieve a slow release for 14 days and exert its bioactivity to promote the proliferation of fibroblasts. The porous scaffolds prepared with polycaprolactone (PCL), and hydroxyapatite (HA) 3D printing have a 300 μm macroporous structure with good biocompatibility. In vivo experiments results demonstrated that the bilayer composite scaffold could promote soft tissue repair of the skull base membrane through the centripetal nanofiber structure and slow-release of bFGF factor. It also played the role of promoting the regeneration of the skull base bone tissue. In addition, the centripetal nanofiber structure also had a promotional effect on the regeneration of skull base bone tissue.

4D Printing: Research Focuses and Prospects

As an emerging technology in the field of additive manufacturing, 4D printing is highly disruptive to traditional manufacturing processes. Therefore, it is necessary to systematically summarize the research on 4D printing to promote the development of related industries and academic research. However, there is still an obvious gap in the visual connection between 4D printing theory and application research. We collected 2070 studies from 2013 on 4D printing from the core collection of Web of Science. We used VOSviewer 1.6.20 and CiteSpace software 6.3.3 to visualize the references and keywords to explore focuses and trends in 4D printing using scientometrics. In addition, real-world applications of 4D printing were analyzed based on the literature. The results showed that “tissue engineering applications” is the most prominent focus. In addition, “shape recovery”, “liquid crystal elastomer”, “future trends”, “bone tissue engineering”, “laser powder bed fusion”, “cervical spine”, “4D food printing”, “aesthetic planning” are also major focuses. From 2013 to 2015, focuses such as “shape memory polymers” and “composites” evolved into “fabrication”. From 2015 to 2018, the focus was on “technology” and “tissue engineering”. After 2018, “polylactic acid”, “cellulose”, and “regenerative medicine” became emerging focuses. Second, emerging focuses, such as polylactic acid and smart polymers, have begun to erupt and have become key research trends since 2022. “5D printing”, “stability” and “implants” may become emerging trends in the future. “4D + Food”, “4D + Cultural and Creative”, “4D + Life” and “4D + Clothing” may become future research trends. Third, 4D printing has been widely used in engineering manufacturing, biomedicine, food printing, cultural and creative life, and other fields. Strengthening basic research will greatly expand its applications in these fields and continuously increase the number of applicable fields.

The Utilization of Central Composite Design for the Production of Hydrogel Blends for 3D Printing

Central composite design (CCD) is a statistical experimental design technique that utilizes a combination of factorial and axial points to study the effects of multiple variables on a response. This study focused on optimizing hydrogel formulations for 3D printing using CCD. Three biopolymers were selected: sodium alginate (SA), gelatin (GEL), and carboxymethyl cellulose (CMC). The maximum and minimum concentrations of each polymer were established using a Google Scholar search, and CCD was employed to generate various combinations for hydrogel preparation. The hydrogels were characterized in accordance with their swelling degree (SD) in phosphate-buffered saline (PBS) and Dulbecco’s Modified Eagle Medium (DMEM), as well as their printability in 2D and 3D assays. The formulation consisting of 7.5% SA, 7.5% GEL, and 2.5% CMC exhibited the best swelling properties and exceptional printability, surpassing all other tested formulations. This study highlights the effectiveness of design of experiment methodologies in accelerating the development of optimized hydrogel formulations for various applications in 3D printing and suggests avenues for future research to explore their performance in specific biological contexts.

Current Applications of the Three-Dimensional Printing Technology in Neurosurgery: A Review.

In the recent years, three-dimensional (3D) printing technology has emerged as a transformative tool, particularly in health care, offering unprecedented possibilities in neurosurgery. This review explores the diverse applications of 3D printing in neurosurgery, assessing its impact on precision, customization, surgical planning, and education. A literature review was conducted using PubMed, Web of Science, Embase, and Scopus, identifying 84 relevant articles. These were categorized into spine applications, neurovascular applications, neuro-oncology applications, neuroendoscopy applications, cranioplasty applications, and modulation/stimulation applications. 3D printing applications in spine surgery showcased advancements in guide devices, prosthetics, and neurosurgical planning, with patient-specific models enhancing precision and minimizing complications. Neurovascular applications demonstrated the utility of 3D-printed guide devices in intracranial hemorrhage and enhanced surgical planning for cerebrovascular diseases. Neuro-oncology applications highlighted the role of 3D printing in guide devices for tumor surgery and improved surgical planning through realistic models. Neuroendoscopy applications emphasized the benefits of 3D-printed guide devices, anatomical models, and educational tools. Cranioplasty applications showed promising outcomes in patient-specific implants, addressing biomechanical considerations. The integration of 3D printing into neurosurgery has significantly advanced precision, customization, and surgical planning. Challenges include standardization, material considerations, and ethical issues. Future directions involve integrating artificial intelligence, multimodal imaging fusion, biofabrication, and global collaboration. 3D printing has revolutionized neurosurgery, offering tailored solutions, enhanced surgical planning, and invaluable educational tools. Addressing challenges and exploring future innovations will further solidify the transformative impact of 3D printing in neurosurgical care. This review serves as a comprehensive guide for researchers, clinicians, and policymakers navigating the dynamic landscape of 3D printing in neurosurgery.

Photo‐cationic polymerizable ceramic slurry for the fabrication of ceramic structures in three‐dimensional printing

AbstractCycloaliphatic epoxides exhibit post‐light irradiation heat‐induced polymerization, creating warp‐resistant green bodies during sintering. However, their use in light polymerization three‐dimensional (3D) printing is limited by slow photo‐curing speeds. In this study, a photo‐cationic polymerizable ceramic slurry was developed for 3D printing by mixing oxetane with cyclo‐aliphatic epoxide. This mixture improved photo‐curing speed, reduced resin viscosity, and enhanced the ceramic slurry's solid content. Additionally, we optimized the slurry by considering the specific and content ratio of photosensitizers and light absorbers. The optimized slurry polymerized unreacted functional groups in the polymer, improving the fracture strength of the green bodies through enhanced crosslinking density and uniformity in each layer. Ultimately, a sintered body without warpage was produced by the improved green bodies. This approach provides a solution related to controlling the photocuring speed and expands the potential applications of 3D printing in areas where the precision and stability of the printing material are required.

Low-carbon cementitious composite incorporated with biochar and recycled fines suitable for 3D printing applications: hydration, shrinkage and early-age performance

In recent years, the construction industry has witnessed significant advancements in concrete technology, particularly with the integration of 3D printing in cement-based materials. While this innovation offers promising opportunities for the sector, the high binder and fine particle content of 3D printing mixes presents a substantial environmental challenge due to their considerable carbon footprint. To mitigate this impact, strategies often involve substituting portions of the binder or aggregate with waste materials. This article presents a comparative analysis of two promising approaches to reducing the carbon footprint of 3D printing concrete mixes by partially replacing cement with biochar and recycled fines. The study examines the effects of these materials on the rheological properties and early-age hydration processes of the 3D printing mix. A reference mix (REF) was established, followed by the development of eight additional mixes, with four incorporating biochar and four incorporating recycled fines, each replacing 1.25%, 2.5%, 5%, and 10% of the cement volume. The findings indicate that recycled fines have a neutral effect on the spread flow diameter of the mixture but increase initial deformations in printed elements. Conversely, biochar, due to its water absorption capacity, reduces fluidity, enhancing buildability by enabling faster printing with minimal initial deformation. Additionally, replacing up to 2.5 vol.% of cement with either material accelerates the normalized heat flow, contributing to a quicker gain in mechanical properties. However, biochar increases shrinkage deformations within the first 12 hours, while recycled fines mitigate them. Importantly, replacing up to 10 vol.% of cement with these materials does not significantly compromise early compressive strength.

Personalized Brachytherapy: Applications and Future Directions

Brachytherapy offers a highly conformal and adaptive approach to radiation therapy for various oncologic conditions. This review explores the rationale, applications, technological advances, and future directions of personalized brachytherapy. Integration of advanced imaging techniques, 3D-printed applicators, and artificial intelligence are rapidly enhancing brachytherapy delivery and efficiency, while genomic tests and molecular biomarkers are refining patient and dose selection. Emerging research on combining brachytherapy with immunotherapy offers unique synergistic potential, and technologies such as intensity-modulated and shielded brachytherapy applicators present novel opportunities to further optimize dose distributions. Despite these promising advances, the field faces challenges including a need to train more practitioners and develop new approaches to treating a broader range of malignancies. As personalized medicine evolves, brachytherapy’s ability to deliver highly targeted, individualized treatments positions it as a critical component in future cancer care.

Application of 3D Printing to Design and Manufacture Pancreatic Duct Stent and Animal Experiments.

Objective: Postoperative pancreatic fistula (POPF) is a common and challenging complication following pancreaticoduodenectomy (PD), occurring in 2% to 46% of cases. Despite various pancreaticojejunostomy techniques, an effective method to prevent POPF has not been established. This study aimed to develop and evaluate a novel 3D-printed biodegradable pancreatic duct stent to simplify the surgical process of pancreaticojejunostomy, reduce anastomotic complexity, and minimize postoperative complications. Methods: Data from 32 patients undergoing total laparoscopic pancreaticoduodenectomy were utilized. Preoperative CT scans were transformed into 3D reconstructions to guide the design and printing of customized stents using polylactic acid (PLA). The stents were assessed for mechanical integrity, surface texture, and thermal stability. Animal experiments were conducted on 16 mini pigs, with the experimental group receiving the novel stent and the control group receiving traditional silicone stents. Results: The 3D-printed stents demonstrated accurate dimensional replication and mechanical reliability. In the animal experiments, the experimental group showed no significant difference in postoperative complications compared to the control group. At 4 weeks post-surgery, CT scans revealed well-healed anastomoses in both groups, with no significant inflammation or other complications. Histological examination and 3D reconstruction models confirmed good healing and device positioning in the experimental group. Conclusion: The 3D-printed biodegradable pancreatic duct stent offers a promising solution for pancreaticojejunostomy, with comparable safety and efficacy to traditional methods. Further research is needed to validate its clinical application.

Microencapsulated phase change material in 3D-printable mortars

The present study investigates the potential of replacing sand with microencapsulated phase change materials (MEPCM) in 3D-printable mortar to provide a promising way to improve thermal performance in 3D-printed buildings. Adding MEPCM significantly enhanced the rheological properties and early hardening evolution of cementitious mortar for 3D printing applications without the need for viscosity modifier agents. In hardened mortars, microstructural analysis and thermal cycling experiments confirmed that MEPCM remained intact and stable within the cementitious environment. The thermal properties of the treated mortars, including latent heat and thermal conductivity, were improved for energy-saving applications. Despite this, the compressive strength of the mortars dropped considerably by increasing the concentration of MEPCM while a strength of above 20 MPa was maintained. Simulation results from 3D Finite Element Method (FEM) and 1D reduced order model (ROM) closely matched the experimental data from printed walls in a thermal setup, validating the use of 1D ROM simulations for long-term predictions. In a case study, a printed wall where MEPCM replaced 80 % of the sand showed a ∼40 % reduction in energy consumption compared to mortar without MEPCM under real weather conditions.

Extrusion 3D Printing of Intrinsically Fluorescent Thermoplastic Polyimide: Revealing an Undisclosed Potential.

Thermoplastic polyimides (TPIs) are promising lightweight materials for replacing metal components in aerospace, rocketry, and automotive industries. Key TPI attributes include low density, thermal stability, mechanical strength, inherent flame retardancy, and intrinsic fluorescence under UV light. The application of advanced manufacturing techniques, especially 3D printing, could significantly broaden the use of TPIs; however, challenges in melt-processing this class of polymer represent a barrier. This study explored the processability, 3D-printing and hence mechanical, and fluorescence properties of TPI coupons, demonstrating their suitability for advanced 3D-printing applications. Moreover, the study successfully 3D-printed a functional impeller for an overhead stirrer, effectively replacing its metallic counterpart. Defects were shown to be readily detectable under UV light. A thorough analysis of TPI processing examining its rheological, morphological, and thermal properties is presented. Extruded TPI filaments were 3D-printed into test coupons with different infill geometries to examine the effect of tool path on mechanical performance. The fluorescence properties of the 3D-printed TPI coupons were evaluated to highlight their potential to produce intricately shaped thermally stable, fluorescence-based sensors.

High internal phase Pickering emulsions co-loaded with astaxanthin and ferrous gluconate improve iron deficiency anemia in mice and their applications in 3D printing

Iron deficiency anemia (IDA) is a prevalent and serious nutritional health issue that can be mitigated through dietary iron supplementation. However, only ferrous ions, prone to oxidation, can be absorbed in the gastrointestinal tract. In the current work, the effects of high internal phase Pickering emulsions (HIPPEs) co-loaded with astaxanthin (ASTA) and ferrous gluconate on Fe2+ oxidation, IDA management, and their 3D printing performance were investigated. The results demonstrated that the HIPPEs co-loaded with ASTA and ferrous gluconate effectively reduced the oxidation rate of Fe2+ during storage. Animal studies also revealed that HIPPE co-loaded with ASTA and ferrous gluconate had a therapeutic effect on IDA symptoms in mice. HIPPE co-loaded with ASTA and 400 mg/L ferrous gluconate demonstrated superior efficacy in restoring hemoglobin (Hb) levels, organ coefficients, and histological parameters in mice with IDA. Moreover, the evaluation of the adaptability of HIPPEs co-loaded with ASTA and ferrous gluconate for food 3D printing indicated a slight reduction in printing resolution. Overall printing performance was found to be acceptable and satisfactory. Co-loading ASTA and ferrous gluconate in HIPPEs offers an efficient way to address the oxidation challenge of ferrous ion supplementation, enabling customization and flexibility in the production of iron-fortified foods to mitigate IDA.

Functional Silsesquioxanes-Tailoring Hydrophobicity and Anti-Ice Properties of Polylactide in 3D Printing Applications.

To explore the tailoring of hydrophobicity in 3D-printed polylactide (PLA) composites for advanced applications using additive manufacturing (AM), this study focuses on the use of Fused Deposition Modeling (FDM) 3D printing. PLA, a material derived from renewable sources, is favored for its eco-friendliness and user accessibility. Nonetheless, PLA's inherent hydrophilic properties result in moisture absorption, negatively affecting its performance. This research aims to modify PLA with organosilicon compounds to enhance its hydrophobic and anti-icing properties. Incorporating fluorinated siloxane derivatives led to significant increases in water contact angles by up to 39%, signifying successful hydrophobic modification. Mechanical testing demonstrated that the addition of organosilicon additives did not compromise the tensile strength of PLA and, in some instances, improved impact resistance, especially with the use of OSS-4OFP:2HEX:2TMOS, which resulted in an increase in the tensile strength value of 25% and increased impact strength by 20% compared to neat PLA. Differential scanning calorimetry (DSC) analysis indicated that the modified PLA exhibited reduced cold crystallization temperatures without altering the glass transition or melting temperatures. These results suggest that organosilicon-modified PLA has the potential to expand the material's application in producing moisture and ice-resistant 3D-printed prototypes for various industrial uses, thereby facilitating the creation of more durable and versatile 3D-printed components.

Polymer microsphere inks for semi-solid extrusion 3D printing at ambient conditions

Extrusion-based 3D printing methods have great potential for manufacturing of personalized polymer-based drug-releasing systems. However, traditional melt-based extrusion techniques are often unsuitable for processing thermally labile molecules. Consequently, methods that utilize the extrusion of semi-solid inks under mild conditions are frequently employed. The rheological properties of the semi-solid inks have a substantial impact on the 3D printability, making it necessary to evaluate and tailor these properties. Here, we report a novel semi-solid extrusion 3D printing method based on utilization of a Carbopol gel matrix containing various concentrations of polymeric microspheres. We also demonstrate the use of a solvent vapor-based post-processing method for enhancing the mechanical strength of the printed objects. As our approach enables room-temperature processing of polymers typically used in the pharmaceutical industry, it may also facilitate the broader application of 3D printing and microsphere technologies in preparation of personalized medicine.

Structural build-up of 3D printed earth by drying

In recent years, the potential of earth materials in construction has emerged as a sustainable pathway, offering environmental benefits compared to traditional methods. When used in raw form, earth materials can be recycled at the end of a building life, reducing construction waste. In parallel, integrating additive manufacturing into the architecture, engineering, and construction (AEC) sector has brought about a shift in construction dynamics, combining efficiency with precision. This paper bridges the study of 3D printing with earth-based fresh mortars, emphasising the capabilities of the “Forced Layer Drying” (FLD) technique in the additive manufacturing process to increase the mechanical performance of the printing mortar.This paper begins by defining the requisite rheological properties for successful 3D printing. A chosen material for this paper is speswhite kaolin. An instrumental aspect of our research is exploring an established model for the drying rate of saturated porous media, such as earth and concrete, and its application to predict the evaporation rate of saturated earth-based mortar in 3D printing with forced drying conditions. The Wind-Tunnel experiment was conducted to validate this model, examining the interplay of airflow speed and temperature on the evaporation rate. Further deepening this study, the soil water content and undrained shear strength are correlated, specifically based on models derived from oedometer geotechnical standard tests. This facilitated a comprehensive understanding of porous earth-based materials in various moisture scenarios. Our findings confirm that airflow, temperature, and the geometry of the printed object play instrumental roles in affecting evaporation rate, consequent mechanical performance, and structural build-up of the material. The paper wraps up by offering insights into the practical application of 3D printing using earth-based mortars, with a special focus on FLD technique.

The Comparison Between Traditional Versus 3D Printing Combined With Computer Navigation Technique in the Management of Orbital Blowout Fractures.

Three-dimensional printing (3D printing) technology and computer navigation technology have been gradually applied in surgeries for orbital blowout fractures. This study compared the efficacy of traditional techniques (group I) and 3D printing combined with computer navigation technology-assisted techniques (group II) in the management of orbital blowout fractures. All patients treated for orbital blowout fractures in the Affiliated Hospital of Yangzhou University from March 2018 to February 2021 were reviewed. The primary predictive variable was surgical techniques used for orbital fractures (traditional techniques or 3D printing combined with computer navigation technology-assisted techniques). Outcome variables included diplopia, limitation of extraocular muscle movement, and enophthalmos orbital volume. All the surgeries were successfully performed without serious complications. Six months after the operation, the degree of diplopia and limitation of extraocular muscle movement in the traditional techniques group and 3D printing combined with computer navigation technology-assisted techniques group were significantly improved (the former Z= -2.670, P=0.008, the latter Z=-3.584, P<0.001 and the former Z=-4.852, P<0.001, the latter Z=-5.427, P<0.001, respectively). There were no significant differences in the degree of diplopia and limitation of extraocular muscle movement between the 2 groups before the operation (the former Z=-0.842, P=0.400; the latter Z=-0.567, P=0.571), and there were significant differences after the operation (the former Z=-2.773, P=0.006; the latter Z=-2.892, P=0.004), and the 3D printing combined with computer navigation technology-assisted techniques group showed an advantage over the traditional techniques group. The difference in bilateral enophthalmos and orbital volume in traditional techniques groups and 3D printing combined with computer navigation technology-assisted techniques groups was dramatically decreased (the former t=12.558, P<0.001, the latter t=12.659, P<0.001, and the former t=19.194, P<0.001, the latter t=17.770, P<0.001, respectively). There were no significant differences in bilateral enophthalmos and orbital volume between the 2 groups before the operation (the former t=-0.410, P=0.683; the latter t=0.311, P=0.756), and there were significant differences after the operation (the former t=4.081, P<0.001; the latter t=4.078, P<0.001). There were statistically significant differences in surgical time and cost between the traditional technology group and the 3D printing combined with computer navigation technology-assisted technology group (the former t=8.445, P<0.001, and the latter t=3.534, P<0.001); 3D printing combined with computer navigation technology-assisted techniques group spent more surgical time and money than the traditional techniques group. The application of 3D printing combined with computer navigation techniques in the management of orbital blowout fractures can significantly improve the accuracy and safety of the operation. 3D printing combined with computer navigation technology-assisted techniques group spent more surgical time and money.

3D-printed gradient conductivity and porosity structure for enhanced absorption-dominant electromagnetic interference shielding

The application of 3D printing for the development of electromagnetic interference (EMI) shielding materials is currently constrained by a limited range of material options and design schemes. In this work, we developed conductivity-modulated polylactic acid (PLA)-MXene composite filaments for fused deposition modeling (FDM) 3D printing, demonstrating excellent printability and durability. Utilizing these filaments, we propose a design scheme focused on absorption-dominant EMI shielding materials. Our design features non-conductive PLA with larger pores at the incident surface, transitioning to layers with increasing conductivity and decreasing pore sizes. This gradient structure minimizes reflection by providing impedance matching and enhances absorption by extending the propagation path of EM waves through multiple reflections and scattering within the pores. Additionally, interfacial polarization effects between air, PLA, and MXene nanoflakes strengthen the absorption mechanisms. Both simulation and experimental results confirm that the combined gradient conductivity and pore size structures significantly improve EMI shielding effectiveness (EMI SE) and absorptivity, achieving an EMI SE of 65 dB and an absorptivity of 0.76 in the X-band. Our findings underscore its potential to create adaptable, high-performance EMI shields suitable for complex geometries and reducing secondary interference.