Printing Model Research Articles

Transcatheter closure of paravalvular leakage through multiple approaches after surgical mechanical valve replacements: A retrospective study

Background: Transcatheter closure of percutaneous paravalvular leak (PVL) is a technically challenging procedure, especially after surgical mechanical valve replacements (SMVR), as the risk of interference with the prosthetic valve discs and the complex interventional techniques required for mitral PVL closure. Our study was designed to review the results with transcatheter closure of PVL after SMVR. Methods: From January 2018 through December 2023, a total of 64 patients with PVL after SMVR underwent transcatheter closure with the help of preoperative 3-dimensional printing model and simulator for image evaluation. We reviewed the catheter techniques, perioperative characteristics, and prognosis. Results: The median follow-up was 28 (3–58) months. The procedure was successful in 60/64 (93.8%) patients. There were 36 aortic PVLs, 27 mitral PVLs, and 1 combined aortic and mitral PVL which were repaired by the transcatheter approach. A total of 24 patients had aortic valve replacements and 20 patients had mitral valve replacements, while 20 patients had previously combined aortic and mitral valve replacements. Procedural time was 35 to 300 (106.6±51.2) minutes. Fluoroscopic time was 8 to 50 (17.6±11.3) minutes. The hospital stay was 5 to 21 (8.1±3.5) days. A total of 47 (78.3%) patients improved by ≥1 New York Heart Association functional class at the 1-year follow-up. Conclusion: Complex catheter techniques were included in percutaneous closure of mechanical PVL. However, this minimally closure treatment could provide reliable outcomes and shorter hospital stays in selected patients.

Digital design combined with endoscopic minimally invasive extraction of impacted mandibular third molars with roots in contact with the mandibular canal

Objective: To study the clinical efficacy of digital design combined with three-dimensional (3D) printing model minimally invasive extraction of complex impacted mandibular third molars. Methods: Eight patients who visited the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from April 2023 to March 2024 were included, including 3 males and 5 females, aged from 27 to 57 years old. The impacted mandibular third molars of all patients were closely related to the mandibular canal, and part of the dental tissue entered the mandibular canal. Preoperative digital design was used to simulate the intraoperative tooth segmentation and bone removal operation of the power system and the segmented tooth dislocation path, and analyze the tooth extraction resistance. The mandibular teeth, mandibular canal and mandibular model were three-dimensionally printed using light-curing resin inkjet. During the operation, an endoscope was used combined with the 3D printed model to minimally invasively extract the impacted mandibular third molar. Quantitative sensory testing of the patient's lower lip skin on the operated side was performed before surgery, 2 days after surgery, and 7 days after surgery. Clinical data such as operation time were collected. A paired sample t test was performed on the 2 and 7 days postoperative data and the preoperative data to compare the data differences. Results: All 8 patients successfully completed preoperative design, model printing and minimally invasive surgery. The number of teeth segmented in the preoperative design was (4.4±1.3), and the number of teeth segmented in the actual operation was (4.0±1.1). The operation time was (33.3±13.0) min. None of the patients had postoperative numbness of the lower lip or other postoperative complication. It was observed endoscopically that the inferior alveolar neurovascular bundle was exposed in the extraction socket during the operation. The patient's pressure pain threshold 2 days after surgery (0.601±1.170) was significantly lower than before surgery (1.251±1.109) (t=2.83, P=0.025). Conclusions: For complicated impacted mandibular third molars, digital design combined with 3D printing model can be used to perform minimally invasive extraction with the assistance of an endoscope.

A Low-Cost Workflow to Generate Virtual and Physical Three-Dimensional Models of Cardiac Structures.

Three-dimensional modeling and printing (3DMP) of anatomical structures from cross-sectional imaging data can enhance the understanding of spatial relationships in complex congenital heart defects. Partially due to the substantial financial, material and personnel resources required, 3DMP is not yet universally used. Here, we describe a workflow that addresses and eliminates these drawbacks. The workflow utilizes the open-source software "3D Slicer" (The Slicer Community) and "Blender" (Blender Foundation) for segmentation and post-editing of datasets. This approach enables the generation of virtual or physical 3D models. The physical models are printed using a standard fused deposition modeling printer. The financial challenges that likely constrain the wider use of 3DMP are largely addressed by this approach. However, the workflow still requires a considerable amount of time to manually segment the imaging data. Three-dimensional modeling and printing might improve planning and safety of congenital cardiac surgical treatment. Furthermore, it is a useful tool for education of parents and medical professionals. This workflow increases its suitability for routine use also in regions with low economic resources.

A neurosurgical nursing training system based on 3D printing models: practice and exploration of precision medicine

BackgroundIn recent years, the concept of precision medicine has gradually permeated the field of nursing, presenting new challenges for neurosurgical nursing staff. Traditional teaching methods often struggle to adequately convey complex anatomical knowledge and nursing skills, thereby affecting the learning outcomes and clinical decision-making abilities of nurses. As an innovative educational tool, three-dimensional (3D) printing technology has demonstrated significant potential in medical education in recent years. Therefore, this project aims to explore the advantages and feasibility of using 3D printed models as a novel teaching tool in neurosurgical nursing.MethodsThe study involved 80 nursing personnel who participated in the neurosurgical rotation training at Shaoxing People’s Hospital from 2022 to 2023. The control group (40 individuals) used only traditional teaching tools such as textbooks, multimedia courseware, and laboratory equipment for theoretical and practical training based on the curriculum. The experimental group (40 individuals) incorporated a 3D printing model database as an innovative teaching tool on the basis of traditional teaching methods, and used patient-specific 3D printed models for precise nursing training. After the training, both groups were assessed for theoretical and practical abilities, professional values, job satisfaction, and the prognosis of intracranial aneurysm patients they cared for.ResultsThe experimental group demonstrated superior scores in theoretical and practical abilities, professional values, and job satisfaction compared to the control group. During the training period, patients with intracranial aneurysms receiving precision nursing care from the experimental group showed better quality of life and neurological functional outcomes compared to the control group.ConclusionsThe nursing training system based on 3D printing models can enhance the learning efficiency and nursing work satisfaction of nursing personnel. It may have a positive impact on the professional values of nursing personnel, thereby laying a solid foundation for providing high-quality, precise nursing services in the field of neurosurgery in the future.

Two-step fabrication of clear view SLA millifluidic device for long-term in-vitro cultures

Purpose In vitro millifluidic cultures with perfusion are essential tools to analyse and understand the interactions between cells, their matrix and multi-cell populations. The purpose of this paper is to focus on the design and development of a 3D-printed template that can be used for fabrication of a clear view poly (dimethyl siloxane) (PDMS) device. The major objective is to obtain a transparent device prototype that allows perfusion culture of two cell types for multiple days that can be imaged using laser scanning confocal microscopy. Design/methodology/approach The authors used a two-step approach for achieving the final geometric structure at a faster timeline and lower cost. The first part focuses on comparing the fidelity of the printing templates using fused deposition modelling (FDM) and stereolithography (SLA) printers for a range of dimensions. They then show that the complex geometry chip with connection chambers can be printed using low resolution low cost FormLab SLA printer. The final optimized design was then printed using high-resolution Projet 6000 SLA printer to obtain smoother structures. Findings In this work, the authors have shown that the FormLab SLA printer yields significantly lower error for printing complex design geometries as compared to FDM printer. Result shows that FormLab printer can be used to achieve a minimum dimension of 0.5 mm. They then use the printer to optimize the device dimension for the culture chip which requires several iterations of printing and experimenting. They showed the two-step protocol of printing the optimized template in a high-resolution SLA printer and further fabricating a clear view millifluidic PDMS device that is compatible confocal microscopy imaging. They used this culture chip for perfusion culture of two cell type, and the controlled fluidic exchange between the two chambers led to the formation of neuroglia junction. Originality/value One of the major bottlenecks for obtaining complex geometry in mili/microfluidic device by 3D printing is the need of multiple iterations on printing. This makes the tuning of dimension significantly expensive. Another challenge is to obtain a smooth surface of PDMS that leads to a leak proof clear view device compatible for laser based confocal imaging. The combination of two printers plays a crucial role for the rapid prototyping of the imaging device with flow control. The proposed approach lowers the cost for prototyping of in vitro culture chip with complex geometries to improve on biological research demanding multi-chamber fluidic device.

The accuracy and efficiency of design and development of 3D printed integral anatomical acetabular prosthesis in total hip arthroplasty for Crowe type Ⅱ and Ⅲ developmental dysplasia of the hip

Objective: To compare the accuracy and efficiency between the model development method and the software development method, which design and develop 3D printed integral anatomical acetabular prosthesis to be used in total hip arthroplasty(THA) for patients with Crowe type Ⅱ and Ⅲ developmental dysplasia of the hip(DDH). Methods: Fifteen patients with end-stage hip osteoarthritis due to Crowe type Ⅱ and Ⅲ DDH who underwent THA in the Orthopedics Department of the First Affiliated Hospital of Bengbu Medical College between January 2015 and June 2023 were selected in this study retrospectively. There were 1 male (1 hip) and 14 females (17 hips) with a mean age of (55.1±9.1) years. There were 12 hips with Crowe type Ⅱ, 6 hips with Crowe type Ⅲ. The preoperative pelvis three-dimensional CT data in those patients were used to design integral anatomical acetabular prosthesis. The model development group used 3D printing technology to print life-size pelvis models. The acetabulum was reamed and the acetabulum cup was inserted into the socket according to conventional THA procedures. The bone defect above the acetabulum cup was filled with bone wax. The Mimics and 3-matic software were used to simulate the THA procedures, design and install the integrated anatomical acetabular prosthesis in the software development group. The operation time, the size of the acetabular cup, the volume and surface area of the acetabulum bone defect, the acetabular cup's inclination and anteversion, the horizontal distance and the vertical distance of hip rotation center were compared between the two methods. Results: The study in the two groups were all based on the data of 18 hips in the 15 patients. The horizontal and vertical distances of rotation center in the model development group and software development group was (32.08±1.80) mm, (32.17±2.40) mm and (14.36±1.53) mm, (15.11±1.45) mm, respectively (both P>0.05). The cup size in model development group was (48.56±1.15)mm, and it was (48.77±1.22) mm in the software group (P=0.160). The anteversion and inclination of the acetabular cup in the model and software groups were 23.79°±6.31°, 30.49°±11.03° and 15.17°±0.52°, 40.24°±0.58°, respectively (both P<0.01). The volume and surface area of the acetabulum bone defect in the model development group was (5.06±2.86) mm3 and (8.31±2.21) mm2, respectively, while it was (4.01±2.56)mm3 and (6.83±2.71) mm2, respectively, in the software development group (both P<0.05). The work time in the model development group was (24.43±0.68) h and (0.47±0.12) h in the software development group, respectively (P<0.001). Conclusion: Compared with the 3D printing model development method, the application of Mimics and 3-matic software to design and develop integrated anatomical acetabular prosthesis in total hip arthroplasty for Crowe type Ⅱ and Ⅲ DDH show advantages of convenience, high efficiency and more accuracy.

Pre-Surgical Planning Using Virtual And 3D Printing Model as Guidance for SECONDARY Mandible Reconstruction with Bone Graft: A Case Report

Reconstruction of mandibular defects due to trauma or tumor resection is a significant challenge for surgeons, given the unique and variable shape of the mandible in terms of curvature, length, and height. Numerous techniques have been developed to achieve both aesthetic and functional outcomes. This case report presents a 28-year-old patient with mandibular irregularity following ameloblastoma dissection, which was reconstructed with non-vascularized bone grafts (NBGs) from the left iliac crest approximately 10 years ago. Prior to our procedure, virtual planning and 3D modeling were employed to accurately assess the bone defect. After debridement, a 5 cm defect was identified, and NBGs were harvested from the right iliac crest for reconstruction. NBGs are commonly used for small mandibular defects (&lt;6 cm), non-continuity defects, and benign pathologies, and they can be performed in centers without microsurgical expertise. The use of virtual planning and 3D printing enables the surgical team to thoroughly study the case, anticipate potential issues, and improve precision, resulting in better outcomes and reduced operative time. NBGs, guided by virtual planning and 3D modeling, prove to be an effective technique in reducing surgical time and minimizing the risk of failure during the postoperative recovery period.

Comparative analysis of mechanical and drilling properties: Human skull vs. 3D-printed replicas for neurosurgical training

Neurosurgery is one of the most difficult surgical disciplines, making neurosurgical simulation crucial for learners. 3D printing is increasingly used for this simulation due to its accessibility and cost-effectiveness compared to conventional methods. Previous studies have qualitatively evaluated the efficacy of 3D printing models for burr hole and craniotomy simulation using surgeon feedback. This study quantitatively evaluates the mechanical properties of human skulls and compares them with 3D-printed skulls to identify the necessary materials and technologies for accurate replication in neurosurgical training. Vickers hardness, compression, and drilling simulation tests were conducted on human cadaveric skulls and 3D-printed models manufactured using Fused Filament Fabrication (FFF), Stereolithography (SLA), and Material Jetting (MJ) technologies. Uniaxial force during a simulated burr hole procedure was measured as drilling progressed through the outer table (OT), diploë and inner table (IT) of the skull. The results showed that different 3D printing technologies and materials have qualities corresponding to each of the three layers of the human skull. For instance, the White Resin 40 model was the closest match to the OT of human skull, exhibiting the lowest mean difference of drilling modulus of 1.98. The OT of the human skull had a Vickers hardness of 38.6 ± 5 HV0.05. The closest 3D-printed models were SLA White at 16.6 ± 0.3 HV0.05 and Rigid 10K at 65.7 ± 3 HV0.05. In terms of mechanical properties, the human skull demonstrated a compression modulus that closely matched the SkullSTN 2, PC 60, PEEK 40, and PEEK 60, with differences of less than 0.1 GPa. These findings demonstrate the effectiveness of drilling simulation tests in evaluating various materials and infills to refine models before neurosurgeon evaluation, enabling the identification of an optimal 3D-printed training model for simulating burr hole procedures.

Neuroendoscopy Training

AbstractNeuroendoscopy can be learnt by assisting or doing live human surgery, cadaver dissection with or without augmented pulsatile vessel and cerebrospinal fluid (CSF) perfusion, and practicing on live animal, dead animal model, synthetic models, three-dimensional printing model with or without augmentation with animal, cadaver tissue, pulsatile vessel and reconstructed CSF model, virtual reality (VR) simulator, and hybrid simulators (combined physical model and VR model). Neurosurgery skill laboratory with basic and advanced learning should be there in all teaching hospitals. Skills can be transferred from simulation model or VR to cadaver to live surgery. Staged learning (first with simple model to learn basic endoscopic technique, then animal model, and then augmented cadavers) is the preferred method of learning. Although most surveys favor live surgery and practice on animal models and cadavers as the most preferred training model now, in future VR may also become a favored method of learning. This article is based on our experience in over 10,000 neuroendoscopic surgeries, and feedback from over 950 neuroendoscopic fellows or consultants who attended workshops conducted every 6 monthly since 2010. A literature search was done on PubMed and Google Scholar using (neuroendoscopy) AND (learning), and (neuroendoscopy) AND (training), which resulted in 121 and 213 results, respectively. Out of them, 77 articles were finally selected for this article. Most of the training programs typically focus on microneurosurgical training. There is lack of learning facilities for neuroendoscopy in most centers. Learning of neuroendoscopy differs greatly from microneurosurgery; switching from microneurosurgery to neuroendoscopy can be challenging. Postgraduate training centers should have well-equipped neuroendoscopy skill laboratory and the surgical educational curriculum should include neuroendoscopy training. Learning endoscopy is about taking advantages of the technique and overcoming the limitations of endoscopy by continuous training.

Material selection and design of intake blades for aircraft engines based on additive manufacturing

Abstract The intake blades of aircraft engines are mainly used to capture and guide external air into the engine and are the foundation of engine operation. Their materials and design are related to the performance level and reliability of the entire engine. The “additive” 3D printing manufacturing method has the advantages of high precision, low cost, less material waste, strong design, and a short research and development cycle. This article proposes the use of GH4169 high-temperature alloy as the 3D printing material for the service requirements of aircraft engine intake blades, constructs a 3D printing model, and designs and realizes the 3D printing of engine intake blades.

Artificial Intelligence‐Augmented Additive Manufacturing: Insights on Closed‐Loop 3D Printing

The advent of 3D printing has transformed manufacturing. However, extending the library of materials to improve 3D printing quality remains a challenge. Defects can occur when printing parameters like print speed and temperature are chosen incorrectly. These can cause structural or dimensional issues in the final product. This review investigates closed‐loop artificial intelligence‐augmented additive manufacturing (AI2AM) technology that integrates AI‐based monitoring, automation, and optimization of printing parameters and processes. AI2AM uses AI to improve defect detection and prevention, improving additive manufacturing quality and efficiency. This article explores generic 3D printing processes and issues using existing research and developments. Next, it focuses on fused deposition modeling (FDM) printers and reviews their parameters and issues. The current remedies developed for defect detection and monitoring in FDM 3D printers are presented. Then, the article investigates AI‐based 3D printing monitoring, closed‐loop feedback systems, and parameter optimization development. Finally, closed‐loop 3D printing challenges and future directions are discussed. AI‐based systems detect and correct 3D printing failures, enabling current printers to operate within optimal conditions and minimizing the risk of defects or failures, which in turn leads to more sustainable manufacturing with minimum waste and extending the library of materials.

Study on Printability Evaluation of Alginate/Silk Fibroin/Collagen Double-Cross-Linked Inks and the Properties of 3D Printed Constructs.

In recent years, biological 3D printing has garnered increasing attention for tissue and organ repair. The challenge with 3D-printing inks is to combine mechanical properties as well as biocompatibility. Proteins serve as vital structural components in living systems, and utilizing protein-based inks can ensure that the materials maintain the necessary biological activity. In this study, we incorporated two natural biomaterials, silk fibroin (SF) and collagen (COL), into a low-concentration sodium alginate (SA) solution to create novel composite inks. SF and COL were modified with glycidyl methacrylate (GMA) to impart photo-cross-linking properties. The UV light test and 1H NMR results demonstrated successful curing of silk fibroin (SF) and collagen (COL) after modification and grafting. Subsequently, the printability of modified silk fibroin (RSFMA)/SA with varying concentration gradients was assessed using a set of three consecutive printing models, and the material's properties were tested. The research results prove that the addition of RSFMA and ColMA enhances the printability of low-concentration SA solutions, with the Pr values increasing from 0.85 ± 0.02 to 0.90 ± 0.03 and 0.92 ± 0.02, respectively, and the mechanical strength increasing from 0.19 ± 0.01 to 0.28 ± 0.01 and 0.38 ± 0.01 MPa; cytocompatibility has also been improved. Furthermore, rheological tests indicated that all of the inks exhibited shear thinning properties. CCK-8 experiments demonstrated that the addition of ColMA increased the cytocompatibility of the ink system. Overall, the utilization of SF and COL-modified SA materials as inks represents a promising advancement in 3D-printed ink technology.

Methods for optimizing additive technologies using the example of loaded plastic products

The article describes the development of methods for optimizing additive technologies (FDM printing), taking into account the loads acting on the body in question, in order to save materials and reduce production time, within the framework of robotics, shipbuilding and the development of water, land and air drones. An analysis of existing modification methods to strengthen models was carried out. Various methods of modifying 3D models for printing have been tested. Based on the tests, a universal method for strengthening parts for three-dimensional printing was proposed and developed. The method is based on the principle of creating spherical cavities inside the part in place of the most loaded areas of the part, which then, when creating G-code programs for the printer, will be surrounded by outer plastic walls, creating a seal inside the part. Inventor and Ansys stress analysis and topology analysis are used to identify areas requiring optimization, based on the results of which 3D models of the most loaded areas, or models of areas requiring reinforcement, were created. A software and hardware complex has been created for modifying three-dimensional models for 3D printing and a software has been developed to automate the main parts of the processing technique for finished parts - creating cavities based on a three-dimensional model of loaded zones.

Фотонные кристаллы: оптимизация характеристик и перспективы оптических приложений

Background: Photonic crystals (PCs) have emerged as a new material for light manipulation, providing unprecedented control over light-matter interaction. This unique capacity is due to their periodic dielectric structure, which may produce photonic band gaps that impact photon transmission. Objective: The article summarizes current advances in photonic crystal design and use, focusing on their significance in creating next-generation optical systems. Methods: The article performed a complete literature analysis, concentrating on the most recent PC production and characterization approaches. Innovative techniques like 3D printing, nanoimprint lithography, self-assembly, and advanced computational modelling were studied in depth to optimize their optical characteristics. Results: Recent studies show that PC manufacturing accuracy has increased significantly, allowing for more effective light manipulation and enhanced optical device functioning. Applications such as ultrasensitive sensors, improved optical fibers, and innovative laser designs demonstrate PCs' rising value. Conclusion: The ongoing advancement of photonic crystal technology is laying a solid basis for the next generation of optical devices. These developments improve existing applications and provide opportunities to investigate new functionality in optical and other electromagnetic systems. Incorporating PCs into numerous technical sectors holds the prospect of significant advances in both commercial and scientific fields.

Innovative External Cranial Devices for Protecting a Craniectomy Site: A Scoping Review on Noninvasive Approaches for Patients Awaiting Cranioplasty.

Decompressive craniectomy (DC) is a commonly performed procedure to alleviate high intracranial pressure. To enhance patient quality of life and minimize complications after DC in patients awaiting cranioplasty (CP), multidisciplinary teams have designed and implemented external protective prototypes, including 3-dimensional printing and plaster models, whenever feasible. The aim of this scoping review was to assess the evidence available on innovative external cranial devices that protect the craniectomy site for patients who have undergone DC while awaiting CP in high-income countries and low- and middle-income countries. This scoping review was conducted following the methodology outlined by the Joanna Briggs Institute. Searches were performed in databases such as MEDLINE, Embase, Web of Science, Scielo, Scopus, and World Health Organization Global Health Index Medicus. Patent documents were also searched in Espacenet, Google Patents, and World Intellectual Property Organization. This scoping review included external protective devices for adult patients who underwent DC and CP, while invasive devices were excluded. A total of 9 documents described external cranial devices, with 7 of them led by researchers from high-income countries, including the United States (n = 4), Singapore (n = 1), the United Kingdom (n = 1), and Hong Kong SAR, China (n = 1). Among these devices, 77.7% (n = 7) were created using 3-dimensional printing, while 22.3% (n = 2) were developed through plaster hand modeling. The individual study results were summarized. Sustainable Development Goal (SDG) 3, SDG 9, and SDG 10 play a crucial role in the advancement of innovative strategies to ensure access to essential neurosurgical care, reduce global disparities in treatment outcomes, mitigate postoperative complications, and provide life-saving interventions. This scoping review provides fundamental evidence for multidisciplinary teams involved in designing noninvasive innovations to minimize the risks associated with post-DC complications. It is anticipated that more cost-effective models, particularly in low- and middle-income countries, can be implemented based on the findings of this review.

The Bony Nasal Cavity and Paranasal Sinuses of Big Felids and Domestic Cat: A Study Using Anatomical Techniques, Computed Tomographic Images Reconstructed in Maximum-Intensity Projection, Volume Rendering and 3D Printing Models.

This study aims to develop three-dimensional printing models of the bony nasal cavity and paranasal sinuses of big and domestic cats using reconstructed computed tomographic images. This work included an exhaustive study of the osseous nasal anatomy of the domestic cat carried out through dissections, bone trepanations and sectional anatomy. With the use of OsiriX viewer, the DICOM images were postprocessed to obtaining maximum-intensity projection and volume-rendering reconstructions, which allowed for the visualization of the nasal cavity structures and the paranasal sinuses, providing an improvement in the future anatomical studies and diagnosis of pathologies. DICOM images were also processed with AMIRA software to obtain three-dimensional images using semiautomatic segmentation application. These images were then exported using 3D Slicer software for three-dimensional printing. Molds were printed with the Stratasys 3D printer. In human medicine, three-dimensional printing is already of great importance in the clinical field; however, it has not yet been implemented in veterinary medicine and is a technique that will, in the future, in addition to facilitating the anatomical study and diagnosis of diseases, allow for the development of implants that will improve the treatment of pathologies and the survival of big felids.

Assessment on the influence of FDM process parameters on the mechanical properties of PLA samples

Abstract The manufacturing of functional parts from the fused deposition modeling 3D printer is limited due to poor mechanical properties, low surface finish, and huge production time. During 3D printing of prototypes, the time consumption of printing and mechanical properties of the model is directly proportional. The fused deposition modeling process parameters significantly impact the quality of printed parts. The prime objective of this research is to optimize the process parameters of a 3D printing machine (wall thickness, infill percentage, infill pattern, and infill speed) using polylactic acid material to enhance the mechanical properties with less printing time of the 3D printing model. The ultimate tensile strength and elongation of the 3D printed samples are used to evaluate the mechanical properties of the various slicing process parameters as per the standards. From the results, it is evident that the mechanical properties of the 3D printed materials increased significantly. The magnitude of ultimate tensile strength is reported as 39.972 MPa with a printing time of 28 min. From close observation, it is evident that lower infill speeds with gyroid infill pattern produce the highest ultimate tensile strength of all combinations. Also, optimal results are derived at higher wall thickness and higher infill percentage. In addition to that, finite element analysis was carried out for different infill percentages of the specimen to validate the actual result.

Surface Layer Performance of Low-Cost 3D-Printed Sliding Components in Metal-Polymer Friction

Abstract The paper presents the results of contact strength and tribological property tests of spare parts made of a popular resin using a 3D DLP printing technology. Two printer models by the same manufacturer were used in the study. The post-processing technique, which shapes the final functional properties, was diversified. Surface performance properties were compared, i.e. Shore hardness, indentation hardness, Martens hardness, elastic modulus, and parameters related to surface creep and relaxation. Tribo-logical durability in rotary motion and tribological wear in reciprocating linear motion were also evaluated using micro- and nanotribometers. This was followed by surface analyses of the friction track of the analysed materials using microscopic methods: a scanning electron microscope, a WLI interferometric microscope, and an optical microscope. The results were statistically processed and the relationship between the parameters determined in the indentation test was determined.

Comparison of mechanical properties of 3D printer resins for occlusal splints using different models of 3D printers.

Considering the development of new 3D printing technologies that use different printing techniques, further studies must be conducted to evaluate the impact of different printing systems on the mechanical properties of 3D-printed materials. This study aimed to evaluate the mechanical properties of 3D-printed materials for occlusal devices using different 3D printers and printing layer thicknesses. Ninety rectangular samples were manufactured and divided into nine groups according to the 3D printer model they were printed on (AnyCubic Mono X, Elegoo Mars 2, or FlashForge Hunter) and the layer thickness (20, 50, or 100 µm) and were subjected to superficial microhardness, flexural resistance, and elasticity modulus tests. The results were analyzed using two-way analysis of variance and Tukey's statistical tests, with a significance level of 5%. The type of 3D printer significantly affected superficial microhardness (p = 0.007). Flexural strength showed a significant interaction between the 3D printer and layer thickness (p = 0.005), with both factors independently influencing flexural strength (printer: p< 0.001, layer thickness: p< 0.001). Elasticity modulus was significantly influenced by the 3D printer type (p< 0.001) and the interaction between both factors (p = 0.004). The AnyCubic Mono X 3D printer with a 20 µm layer thickness exhibited more consistent mechanical properties than the other printers. Variations in printing systems and layer thicknesses can impact the mechanical properties of 3D-printed materials. Key words:CAD-CAM. Bruxism. Temporomandibular disorders. Mechanical tests; 3-D printing.Care Team.

Comparative Study of Mechanical Properties and Microstructure Between Conventional and Infinite z-Axis Fused Deposition Modeling Printers

Additive Manufacturing (AM) has emerged as a critical technology in shaping manufacturing strategies, offering versatility and efficiency in designing complex structural components. Extensive literature exists on small- to mid-sized product production. However, a significant knowledge gap exists in manufacturing elongated products, such as wind turbine blades and constructional beams. Current AM technology faces limitations in this context, primarily due to the constraints imposed by the conventional 90-degree nozzle head and limited bed space. This study introduces an innovative AM approach called Infinite z-Axis Printing. This novel technique utilizes a belt-driven heated bed and a 45-degree nozzle head to 3D print objects of infinite length. The study compares this groundbreaking approach and the traditional 90-degree nozzle head Fused Deposition Modeling (FDM) method and the associated results. The findings of this research demonstrate that the Infinite z-Axis Printing methodology yields a significant improvement of up to 20% in tensile and compressive strength compared to the currently used FDM process. This advancement can potentially revolutionize on-site operations by enabling the efficient production of elongated structural components, thus contributing significantly to the construction and renewable energy sectors.