Prospects of 3D Printing Technology in Dental Medicine

With the continuous advancement of technology,the application of 3D printing technology in the field of dental medicine is becoming increasingly widespread.This article aims to explore the current applications and future potential of 3D printing technology in dental medicine and to analyze its benefits and challenges.It first introduces the current state of 3D printing technology in dental implants,crowns,bridges,orthodontics,and maxillofacial surgery.It then discusses the potential applications of 3D printing technology in oral tissue engineering,drug delivery systems,personalized dental prosthetics,and surgical planning.Finally,it analyzes the benefits of 3D printing technology in dental medicine,such as improving treatment accuracy and patient comfort,and shortening treatment times,while also highlighting the challenges faced,such as costs,material choices,and technical limitations.This article aims to provide a reference for professionals in the field of dental medicine and to promote the further application and development of 3D printing technology in this area.

Large-area Flexible Organic Solar Cells: Printing Technologies and Modular Design

Flexibility is the most prominent advantage of organic solar cells(OSCs) compared with traditional photovoltaic devices, showing an irreplaceable commercial potential. Currently, the maximum power conversion efficiencies(PCEs) of single-junction OSCs have been over 19% and 16% upon rigid and flexible substrates, respectively, which meet the criteria for commercial application. Extensive research efforts are under way, such as device configuration design, interface/photosensitive layer synthesis, transparent electrode modification and printing technology innovation, however, the reasonable selection of printing technologies, the huge performance loss of large-area printing process and the structural design of flexible modules are still the bottlenecks, limiting the commercialization of OSCs. This review focuses on the technical challenges and rational modular configuration design for printing preparation of flexible high-efficiency large-area organic devices, from the aspects of the functional layer material selection, printing process research status and large-scale efficiency losses. These will promote the integrated applications of printable organic semiconductor materials for next-generation clean energy and appeal extensive attentions in wearable electronics, building-integrated photovoltaics and Internet of Things, etc.

Advancing Wound Filling Extraction on 3D Faces:An Auto-Segmentation and Wound Face Regeneration Approach

Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical applications.In this paper,we propose an efficient approach for automating 3D facial wound segmentation using a two-stream graph convolutional network.Our method leverages the Cir3D-FaIR dataset and addresses the challenge of data imbalance through extensive experimentation with different loss functions.To achieve accurate segmentation,we conducted thorough experiments and selected a high-performing model from the trainedmodels.The selectedmodel demonstrates exceptional segmentation performance for complex 3D facial wounds.Furthermore,based on the segmentation model,we propose an improved approach for extracting 3D facial wound fillers and compare it to the results of the previous study.Our method achieved a remarkable accuracy of 0.9999993% on the test suite,surpassing the performance of the previous method.From this result,we use 3D printing technology to illustrate the shape of the wound filling.The outcomes of this study have significant implications for physicians involved in preoperative planning and intervention design.By automating facial wound segmentation and improving the accuracy ofwound-filling extraction,our approach can assist in carefully assessing and optimizing interventions,leading to enhanced patient outcomes.Additionally,it contributes to advancing facial reconstruction techniques by utilizing machine learning and 3D bioprinting for printing skin tissue implants.Our source code is available at https://github.com/SIMOGroup/WoundFilling3D.

Biomechanical analysis of an absorbable material for treating fractures of the inferior orbital wall

AIM:To investigate the biomechanical properties and practical application of absorbable materials in orbital fracture repair.METHODS:The three-dimensional(3D)model of orbital blowout fractures was reconstructed using Mimics21.0 software.The repair guide plate model for inferior orbital wall fracture was designed using 3-matic13.0 and Geomagic wrap 21.0 software.The finite element model of orbital blowout fracture and absorbable repair plate was established using 3-matic13.0 and ANSYS Workbench 21.0 software.The mechanical response of absorbable plates,with thicknesses of 0.6 and 1.2 mm,was modeled after their placement in the orbit.Two patients with inferior orbital wall fractures volunteered to receive single-layer and double-layer absorbable plates combined with 3D printing technology to facilitate surgical treatment of orbital wall fractures.RESULTS:The finite element models of orbital blowout fracture and absorbable plate were successfully established.Finite element analysis(FEA)showed that when the Young’s modulus of the absorbable plate decreases to 3.15 MPa,the repair material with a thickness of 0.6 mm was influenced by the gravitational forces of the orbital contents,resulting in a maximum total deformation of approximately 3.3 mm.Conversely,when the absorbable plate was 1.2 mm thick,the overall maximum total deformation was around 0.4 mm.The half-year follow-up results of the clinical cases confirmed that the absorbable plate with a thickness of 1.2 mm had smaller maximum total deformation and better clinical efficacy.CONCLUSION:The biomechanical analysis observations in this study are largely consistent with the clinical situation.The use of double-layer absorbable plates in conjunction with 3D printing technology is recommended to support surgical treatment of infraorbital wall blowout fractures.

Simulation on deposition and solidification processes of 7075 Al alloy droplets in 3D printing technology

In order to study the successive deposition and solidification processes of uniform alloy droplets during the drop-on-demand three dimensional（3D） printing method,based on the volume of fluid（VOF） method,a 3D numerical model was employed.In this model,the 7075 alloy with larger temperature range for phase change was used.The simulation results show that the successive deposition and solidification processes of uniform 7075 alloy droplets can be well characterized by this model.Simulated droplets shapes agree well with SEM images under the same condition.The effects of deposition and solidification of droplets result in vertical and L-shaped ridges on the surface of droplets,and tips of dendrites appear near the overlap of droplets due to rapid solidification.

Three-dimensional printing: review of application in medicine and hepatic surgery

Three-dimensional(3D) printing(3DP) is a rapid prototyping technology that has gained increasing recognition in many different fields. Inherent accuracy and low-cost property enable applicability of 3DP in many areas, such as manufacturing, aerospace,medical, and industrial design. Recently, 3DP has gained considerable attention in the medical field. The image data can be quickly turned into physical objects by using 3DP technology. These objects are being used across a variety of surgical specialties. The shortage of cadaver specimens is a major problem in medical education. However, this concern has been solved with the emergence of 3DP model. Custom-made items can be produced by using 3DP technology. This innovation allows 3DP use in preoperative planning and surgical training. Learning is difficult among medical students because of the complex anatomical structures of the liver. Thus, 3D visualization is a useful tool in anatomy teaching and hepatic surgical training. However,conventional models do not capture haptic qualities. 3DP can produce highly accurate and complex physical models. Many types of human or animal differentiated cells can be printed successfully with the development of 3D bio-printing technology. This progress represents a valuable breakthrough that exhibits many potential uses, such as research on drug metabolism or liver disease mechanism. This technology can also be used to solve shortage of organs for transplant in the future.

The Controlled-releasing Drug Implant based on the Three Dimensional Printing Technology: Fabrication and Properties of Drug Releasing in vivo

Three dimensional （3D） printing technology was utilized to fabricate a new type of drug implant with complicated architectures, employing levofloxacin （LVFX） and rifampicine （RFP） as model drugs. The prepared drug implant prototype consists of a doublelayer structure, of which the upper region is a reservoir system containing RFP and the lower region is a matrix one containing LVFX. The release test in vivo revealed that LVFX was released in the early stage; no RFP was detected until 8th day; both of them continuously released more than 6 weeks. Therefore, 3D printing technology provides a precise and feasible method to fabricate a controlled-releasing drug implant with complicated architectures and this drug implant may present a new strategy for the prophylaxis and treatment of bone diseases such as combined bone infections and bone tuberculosis in the near future.

Experimental investigation on the invert stability of operating railway tunnels with different drainage systems using 3D printing technology

In recent years, the invert anomalies of operating railway tunnels in water-rich areas occur frequently,which greatly affect the transportation capacity of the railway lines. Tunnel drainage system is a crucial factor to ensure the invert stability by regulating the external water pressure(EWP). By means of a threedimensional(3D) printing model, this paper experimentally investigates the deformation behavior of the invert for the tunnels with the traditional drainage system(TDS) widely used in China and its optimized drainage system(ODS) with bottom drainage function. Six test groups with a total of 110 test conditions were designed to consider the design factors and environmental factors in engineering practice,including layout of the drainage system, blockage of the drainage system and groundwater level fluctuation. It was found that there are significant differences in the water discharge, EWP and invert stability for the tunnels with the two drainage systems. Even with a dense arrangement of the external blind tubes, TDS was still difficult to eliminate the excessive EWP below the invert, which is the main cause for the invert instability. Blockage of drainage system further increased the invert uplift and aggravated the track irregularity, especially when the blockage degree is more than 50%. However, ODS can prevent these invert anomalies by reasonably controlling the EWP at tunnel bottom. Even when the groundwater level reached 60 m and the blind tubes were fully blocked, the invert stability can still be maintained and the railway track experienced a settlement of only 1.8 mm. Meanwhile, the on-site monitoring under several rainstorms further showed that the average EWP of the invert was controlled within 84 k Pa, while the maximum settlement of the track slab was only 0.92 mm, which also was in good agreement with the results of model test.

Three-dimensional printing technology for patient-matched instrument in treatment of cubitus varus deformity:A case report

BACKGROUND Recently,medical three-dimensional printing technology(3DPT)has demonstrated potential benefits for the treatment of cubitus varus deformity(CVD)by improving accuracy of the osteotomy through the use of an osteotomy guide,with or without a patient-mated plate.Here,we present an interesting CVD case,involving a patient who was treated with corrective biplanar chevron osteotomy using an innovative customized osteotomy guide and a newly designed patient-matched monoblock crosslink plate created with 3DPT.CASE SUMMARY A 32-year-old female presented with a significant CVD from childhood injury.A computer simulation was processed using images from computerized tomography scans of both upper extremities.The biplanar chevron osteotomy was designed to create identical anatomy between the mirror image of the contralateral distal humerus and the osteotomized distal humerus.Next,the customized osteotomy guide and patient-matched monoblock crosslink plate were designed and printed.A simulation osteotomy was created for the real-sized bone model,and the operation was performed using the posterior paratricipital approach with k-wire positioning from the customized osteotomy guide as a predrilled hole for screw fixation to achieve immediate control of the reduction after osteotomy.Our method allowed for successful treatment of the CVD case,significantly improving the patient’s radiographic and clinical outcomes,with satisfactory result.CONCLUSION 3DPT-created patient-matched osteotomy guide and instrumentation provides accurate control during CVD correction.

Mechanical Experiment for 3D Printing of Titanium Bone Bionic Dental Implants

[Objectives] To explore the flexural strength of 3D printed titanium bone bionic dental implants and provide a scientific basis for the clinical application of 3D printed porous bionic bone dental implants. [Methods] The cone-beam CT( CBCT) image information of 20 premolars extracted by orthodontic requirement was collected,and a new porous bone bionic dental implant was produced using modeling software and 3D printer. The premolars were divided into two groups( A and B). The universal testing machine was used to test the flexural strength of the two groups and the difference in flexural strength between the two groups was compared through statistics. [Results]Twenty 3D printed porous titanium bone bionic implants were accurately produced; the morphology of group A and group B were extremely similar to each other; the average flexural strength of group A was 2 767. 92 N,while the average flexural strength of group B was 778. 77 N,showing that the average flexural strength of group A was significantly higher than that of group B,and the difference was statistically significant( P < 0. 05).[Conclusions]The personalized porous structure root implants produced by 3D printing technology are very similar to the target tooth morphology,and show high accuracy and small error of production. Besides,the flexural strength of 3D printed personalized porous structure root implants can fully meet the requirements of the maximum occlusal force for dental implant restoration. It is expected to provide a scientific basis for clinical application of 3 D printed porous bionic bone tooth implants.

3D Printing Technology for Buildings＇ Accessibility： The Tactile Map for MTE Museum in Pavia

3D printing technology is an innovative manufacturing technology used in several disciplines, whose number and diversity are growing day by day. The development of devices to improve the accessibility of buildings and urban spaces for people with disabilities through 3D priming technology is still not broadly explored. The present study is focused on filling this gap, with the realization of a tactile map of the MTE （Museum of Electrical Technology） of the University of Pavia （Italy） for blind and visually impaired people. The tactile map represents the building plan with all the information to guide the visit. The device is the result of a research process which is made by several steps and experimental tests, aimed at setting the best 3D priming profiles to meet all the requirements of the end-users. This paper describes methods and strategies applied to reach these goals： it underlines the social and technical approaches, the experimental phases and its possible future developments.

Interventional Therapy for Cerebral Aneurysms Under the Guidance of 3D Printing Technology

Objective:To explore the clinical method and effect of 3D printing in the treatment of cerebral aneurysms.Methods:The authors research work on the hospital,work time in February 2019-February 2020,this study selected patients of cerebral aneurysms,this period are selected for treatment of 100 cases of patients,randomly divided into two groups,a group to give simple intervention,named as the control group,another group for the interventional therapy under the guidance of 3 D printing,named as experimental group,analyze the effect of two groups of patients with clinical intervention.Results:The length of hospital stay in the experimental group was shorter than that in the control group.Meanwhile,the incidence of complications and adverse reactions in the experimental group and the control group were 6.00%and 18.00%,the experimental group was better(P<0.05).Conclusion:3D printing technology can be applied in the treatment of patients with cerebral aneurysms to provide guidance for interventional surgical treatment.It has significant effect,can reduce the incidence complications in patients,has significant clinical effect,and can be popularized.

It's Closed In Triumph,'97 International Screen Special Printing Technology Exhibition

’97 Wuhan International Screen Special Printing Technology Exhibition was held from May 21—24, 1997 in Wuhan city,the capital of Hubei Province. 120 famous exhibitors from China, USA, Canada, Holland, Japan, Korea, and Hong Kong, Taiwan districts attended the Exhibition. The booth area was more than 5000 m^2.

An analysis of the development trends of China's printing and printing machinery manufacture technology——Presentation in the International Forum for the Development of Printing Technology

2006 is the commencing year of the Eleventh Five-Year Plan for National Economic and Social Development, and also the fifth anniversary of China joining the World Trade Organization. After the development of the transition period in these years, China’s national economy has successfully inte grated into the global system. National economy remains de- veloping at a high speed. The total amount of import and export reached more than 1.4 trillion USD,

The First International Digital Printing and Image Technology Exhibition & The Sixth International Exhibition of Quick Printing Equipment & Technology

Time: Sept.4-6, 2008Venue: Shenzhen Convention & Exhibition CenterSponsor: Printing and Printing Equipment Industries Association of China (PEIAC)Organizers: The Exhibition Department of

Analysis on the Development of Cigarette Packaging in the Era of Intelligence

China is one of the biggest countries in cigarette production and sales,therefore it is important to improve the quality and efficiency of cigarette production.As cigarette packaging is an important part in cigarette production,therefore,it is important to strengthen research on improving the quality of cigarette packaging.This article summarizes the development process of cigarette packaging in China,introduces the development of printing technology in the era of intelligence,summarizes the application of printing technology in cigarette packaging,analyzes and explores the development trend of cigarette packaging in the era of intelligence,with the hope to provide reference for practitioners.

Design and fabrication of r-hirudin loaded dissolving microneedle patch for minimally invasive and long-term treatment of thromboembolic disease

Cardiovascular disease is the leading cause of global mortality,with anticoagulant therapy being the main prevention and treatment strategy.Recombinant hirudin(r-hirudin)is a direct thrombin inhibitor that can potentially prevent thrombosis via subcutaneous(SC)and intravenous(IV)administration,but there is a risk of haemorrhage via SC and IV.Thus,microneedle(MN)provides painless and sanitary alternatives to syringes and oral administration.However,the current technological process for the micro mould is complicated and expensive.The micro mould obtained via three-dimensional(3D)printing is expected to save time and cost,as well as provide a diverse range of MNs.Therefore,we explored a method for MNs array model production based on 3D printing and translate it to micro mould that can be used for fabrication of dissolving MNs patch.The results show that r-hirudin-loaded and hyaluronic acid(HA)-based MNs can achieve transdermal drug delivery and exhibit significant potential in the prevention of thromboembolic disease without bleeding in animal models.These results indicate that based on 3D printing technology,MNs combined with r-hirudin are expected to achieve diverse customizableMNs and thus realize personalized transdermal anticoagulant delivery for minimally invasive and long-term treatment of thrombotic disease.

Three-dimensional printed talar prosthesis with biological function for giant cell tumor of the talus:A case report and review of the literature

BACKGROUND Giant cell tumors(GCT)are most commonly seen in the distal femur.These tumors are uncommon in the small bones of the hand and feet,and a very few cases have been reported.A giant cell tumor of the talus is rarely seen clinically and could be a challenge to physicians.CASE SUMMARY We report a rare case of GCT of the talus in one patient who underwent a new reconstructive surgery technique using a three-dimensional(3D)printing talar prosthesis.The prosthesis shape was designed by tomographic image processing and segmentation using technology to match the intact side by mirror symmetry with 3D post-processing technologies.The patient recovered nearly full range of motion of the ankle after 6 mo.The visual analogue scale and American Orthopaedic Foot and Ankle Society scores were 1 and 89 points,respectively.CONCLUSION We demonstrated that 3D printing of a talar prosthesis is a beneficial option for GCT of the talus.

A reusable planar triggered spark-gap switch batched-fabricated with PCB technology for medium- and low-voltage pulse power systems

Triggered spark-gap switch is a popular discharge switch for pulse power systems.Previous studies have focused on planarizing this switch using thin film techniques in order to meet the requirements of compact size in the systems.Such switches are one-shot due to electrodes being too thin to sufficiently resist spark-erosion.Additionally,these switches did not employ any structures in securing internal gas composition,resulting in inconsistent performance under harsh atmospheres.In this work,a novel planar triggered spark-gap switch(PTS)with a hermetically sealed cavity was batched-prepared with printed circuit board(PCB)technology,to achieve reusability with low cost.The proposed PTS was inspected by micro-computed tomography to ensure PCB techniques meet the requirements of machining precision.The results from electrical experiments demonstrated that PCB PTS were consistent and reusable with lifespan over 20 times.The calculated switch voltage and circuit current were consistent with those derived from real-world measurements.Finally,PCB PTS was used to introduce hexanitrostilbene(HNS)pellets in a pulse power system to verify its performance.

Research progress of localization technique assisted neuroendoscopy for cerebral hemorrhage

Neurosurgeons who perform intracere-bral hemorrhage(ICH)evacuation procedures have lim-ited options for monitoring hematoma evacuation and intraoperatively assessing residual-hematoma burden.In recent years,neuroendoscope-assisted,minimally inva-sive surgery for spontaneous ICH is simple and effective and becoming increasingly common.Many methods are applied in neuronavigation-assisted surgery for ICH evac-uation,such as neuroendoscopy,three-dimensional(3D)reconstruction,intraoperative ultrasound,and stereotac-tic craniotomy.Compared with a traditional craniotomy operation,hematoma removal(using methods of accurate localization)can reduce iatrogenic damage,protect white matter,and shorten patients’recovery time.This paper mainly outlines the treatment of basal ganglia-cerebral hemorrhage with neuroendoscopy assistance using local-ization techniques.