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.

Anisotropic creep behavior of soft-hard interbedded rock masses based on 3D printing and digital imaging correlation technology

Three-dimensional(3D)printing technology is increasingly used in experimental research of geotechnical engineering.Compared to other materials,3D layer-by-layer printing specimens are extremely similar to the inherent properties of natural layered rock masses.In this paper,soft-hard interbedded rock masses with different dip angles were prepared based on 3D printing(3DP)sand core technology.Uniaxial compression creep tests were conducted to investigate its anisotropic creep behavior based on digital imaging correlation(DIC)technology.The results show that the anisotropic creep behavior of the 3DP soft-hard interbedded rock mass is mainly affected by the dip angles of the weak interlayer when the stress is at low levels.As the stress level increases,the effect of creep stress on its creep anisotropy increases significantly,and the dip angle is no longer the main factor.The minimum value of the long-term strength and creep failure strength always appears in the weak interlayer within 30°–60°,which explains why the failure of the layered rock mass is controlled by the weak interlayer and generally emerges at 45°.The tests results are verified by comparing with theoretical and other published studies.The feasibility of the 3DP soft-hard interbedded rock mass provides broad prospects and application values for 3DP technology in future experimental research.

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.

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.

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.

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.

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.

Found Different Attitude Fracture Characteristics of the NMR Curve by Application of 3D Printing Samples

Nuclear magnetic resonance (NMR) has many advantages, such as little testing time, no harm to rock specimen, and is widely used in the measurement of reservoir pore structure. 3D printing also has many advantages, such as repeating the printing the same attributes samples, forming sample by known rock pore structure, adding different pores or fractures to sample. For the study of fractured reservoir provides a new train of thought by combining NMR and 3D printing. Nuclear magnetic core analysis is an important work in the study of core, using a T2 spectrum at a certain echo time can also be found in the core fractures. The study, by CT scans to establish reservoir pore structure, based on the basic of adding different attitude fracture forming four fracture characteristics of rock sample, using 3D printing for solid sample, through the analysis of the nuclear magnetic resonance (NMR) of these sample, get the response characteristics of fracture characteristics on the T2 curve, the quantitative calculation of fracture porosity of rock sample, the result accord with to establish the model of fracture porosity is very good. For the study of fractured oil and gas reservoir development the new field.

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.

3D printed silicon-based micro-lattices with ultrahigh areal/gravimetric capacities and robust structural stability for lithium-ion batteries

Nanostructured silicon anodes have shown extraordinary lithium storage properties for lithium-ion batteries(LIBs)but are usually achieved at low areal loadings(<1.5 mg·cm^(-2))with low areal capacity.Sustaining sound electrochemical performance at high loading requires proportionally higher ion/electron currents and robust structural stability in the thicker electrode.Herein,we report a three-dimensional(3D)printed silicon-graphene-carbon nanotube(3D-Si/G/C)electrode for simultaneously achieving ultrahigh areal/gravimetric capacities at high mass loading.The periodically arranged vertical channels and hierarchically porous filaments facilitate sufficient electrolyte infiltration and rapid ion diffusion,and the carbonaceous network provides excellent electron transport properties and mechanical integrity,thus endowing the printed 3D-Si/G/C electrode with fast electrochemical reaction kinetics and reversibility at high mass loading.Consequently,the 3D-Si/G/C with high areal mass loading of 12.9 mg·cm^(-2) exhibits excellent areal capacity of 12.8 mAh·cm^(-2) and specific capacity of 1007 mAh·g^(-1),respectively.In-situ optical microscope and ex-situ scanning electron microscope(SEM)confirm that the hierarchically porous filaments with interconnected carbon skeletons effectively suppress the volume change of silicon and maintain stable micro-lattice architecture.A 3D printed 3D-Si/G/C-1||3D-LiFePO_(4)/G full cell holds excellent cyclic stability(capacity retention rate of 78%after 50 cycles)with an initial Coulombic efficiency(ICE)of 96%.This work validates the feasibility of 3D printing on constructing high mass loading silicon anode for practical high energy-density LIBs.

3D打印辅助内侧重建增强固定技术治疗肱骨近端粉碎性骨折的疗效观察

目的探讨3 D打印辅助内侧重建增强固定技术治疗肱骨近端粉碎性骨折的疗效。方法筛选2016年1月-2021年7月入院手术治疗的肱骨近端粉碎性骨折患者68例作为研究对象,并按随机抽样法分两组(每组34例),对照组采用常规内固定治疗,观察组在3 D打印辅助治疗的同时进行内侧支撑重建增强固定技术。对比两组总有效率、关节活动度、Neer评分、CMS评分、Brobery–Morrey功能评分。结果术后68例全部获得随访,随访时间为12~31个月,平均(15.0±3.0)个月。观察组治疗总有效率高于对照组,差异具有统计学意义(P<0.05);观察组的前屈上举、外展、外旋及内翻等活动度均高于对照组,差异有统计学意义(P<0.05),观察组活动度普遍好于对照组;两组治疗前,Neer评分、CMS评分、Brobery–Morrey评分比较,差异无统计学意义(P>0.05),两组治疗后评分均升高,并且观察组评分较对照组均高,差异具有统计学意义(P<0.05),观察组疗效高于对照组。结论3 D打印辅助内侧支撑重建增强固定技术可有效提高肱骨近端粉碎性骨折的手术效果,在提高关节活动度的同时促进肢体各功能恢复,该方法值得借鉴及参考。

Application of 3D-printed prosthesis in revision surgery with large inflammatory pseudotumour and extensive bone defect: A case report

BACKGROUND Hip revision surgery is the final treatment option for the failure of artificial hip joints, but it is more difficult than the initial operation. For patients with hip joint loosening around the prosthesis combined with large inflammatory pseudotumours and large segment bone defects, hip revision is even more difficult, and clinical reports are rare.CASE SUMMARY Male, 59 years old. The patient underwent left hip replacement 35 years ago and was now admitted to hospital due to massive masses in the left thigh, shortening of the left lower extremity, and pain and lameness of the left hip joint. X-ray, computed tomography and magnetic resonance imaging revealed prosthesis loosening, left acetabular bone defect(Parprosky IIIB type), and a bone defect of the left proximal femur(Parprosky IIIA type). Inflammatory pseudotumours were seen in the left hip and left thigh. Hip revision surgery was performed using a 3Dprinted custom acetabular prosthesis was used for hip revision surgery, which was produced by Arcam Electron Beam Melting system with Electron Beam Melting technology. The operation was successful, and the patient was followed up regularly after the operation. The custom-made acetabular prosthesis was well matched, the inflammatory pseudotumour was completely removed, the postoperative hip prosthesis was stable, and the old greater trochanter fracture was well reduced and fixed. The patient was partially weight-bearing with crutches 3 mo after the operation and walked with full weight-bearing after 6 mo. The hip prosthesis was stable, and there was no recurrence of inflammatory pseudotumours at the last follow-up. The Visual Analogue Scale was 3, and the Harris hip score was 90.CONCLUSION The use of 3D-printed personalized custom prostheses for complex hip revision surgery has satisfactory surgical results and has great clinical application value.

Teaching Reform of Building Construction Course under the Background of New Digital Technology

With the advent of the information age,all walks of life have paid more and more attention to the development and application of digital technology.At the same time,the construction industry,which is a traditionally important industry,is not an exception.A series of high-tech digital technologies have been widely used in architectural design and construction,such as BIM technology,3D printing technology,and VR technology.In view of the teaching link of architectural talent training,it is necessary to keep up with the development trend of the digital age,integrate these three kinds of technology into architectural teaching,and impart knowledge to students from planar 2D textbooks to 3D visual digital models,and further transform it from 3D digital to physical perceive or virtual simulation level,and reform teaching methods in all dimensions and in all dimensions to improve teaching effect.In this paper,the feasibility and necessity of integration of the above three architectural digital techniques into the teaching process of"building construction"from the aspects of teaching content,teaching method and teaching evaluation were discussed,and a new teaching model under the background of digital technology was proposed,which has certain teaching reference significance.

Accuracy of Orthodontic 3D Printed Retainers versus Thermoformed Retainers

Background: The integration of the current technology of CBCT and 3D CAD/CAM technology has great potential in the field of orthodontics, which is not yet fully investigated. The purpose of this article is to evaluate the accuracy of 3D printed retainers in comparison to vacuum formed retainers. Methods: Alginate impressions were taken for ten patients who have a CBCT scan. A 3D printed retainer and vacuum formed retainer were fabricated. Linear measure-ments were measured by two assessors using digital caliper. Every measure-ment on the 3D printed retainer was compared to the corresponding measure-ment on the thermoformed retainer. The linear measurements were Inter-canine width, Inter-premolar width (first and second premolars), Inter-molar width, Canine-midline length (both sides) and Canine-molar length (both sides). Intra-observer, and inter-observer reliability measurements were done. Results: Results showed excellent intra-observer reliability for the thermoformed retainer and the 3D printed retainer. Inter-observer measurements showed strong agreement between the measurements of the two assessors, for both retainers. The comparison of the thermoformed retainer to the 3D printed retainer showed high statistical agreement, except for the canine-molar on the right side, but with no clinical significance, p value of 0.038 and mean difference 0.19. Conclusions: The new method for fabricating a 3D printed retainer is accurate and reliable in comparison to the vacuum formed retainer (conventional method). CBCT proved to be efficient for fabrication of a custom made appliances.

3D打印混凝土材料及混凝土建筑技术进展

3D打印是近年来发展起来的高新技术,已在机械制造等行业取得很大成功,在材料和建筑等领域也有所发展。本文在介绍通用3D打印技术进展的基础上,着重阐述了混凝土材料的传统施工工艺、国内外3D打印混凝土技术与其材料和施工工艺的发展现状,讨论了3D打印混凝土当前所面临的问题,并对3D打印混凝土提出了未来展望。

3D打印技术及典型病例数据库在骨科教学中的应用

目的探讨3D打印技术及典型病例数据库在五年制骨科临床教学中的应用和效果。方法按照教学大纲要求筛选合适的骨关节创伤病例,收集临床资料及X-ray、CT等影像资料建立数据库,应用数据库资料及3D打印实物实施教学,与传统教学方法比较授课效果。结果采用3D打印技术及典型病例数据库加深了学生对骨关节创伤知识的理解,有效提高了学习成绩。结论3D打印技术及典型病例数据库的建立,丰富了骨关节损伤的临床教学资源,并使之标准化,能有效提高教学效果,特别有助于学生临床技能的培养和胜任力的提升。

3D打印制造技术发展趋势及对我国结构转型的影响

作为第三次工业革命的重要特征,3D打印制造技术受到广泛关注。对3D打印技术的特征、国内外发展趋势和对我国结构转型影响进行分析,并提出我国3D打印技术发展的战略建议,包括制定推进我国3D打印技术开发应用的国家战略;协同国家科研计划开展3D打印制造技术的研究开发;培养3D打印制造时代的劳动力和创新领军人才;探索3D打印制造技术成果产业化新机制,促进产业链、创新链和价值链的相互融合与发展完善。

3-D打印技术在女性束身衣生产中的应用

为了探讨3-D打印技术在服装生产中的应用价值,通过文献资料的搜集和分析,从服饰品生产中3-D打印技术的应用出发,从结构设计、材料选择、打印设备、后整理技术4个方面阐述了3-D打印女性束身衣的要点,认为其存在材料限制,舒适度低等方面的难点。但是随着3-D打印技术的不断完善以及新型材料的开发,该项技术将来会更为广泛地应用在服装生产领域,从而缩短服装产业链和产品生产的周期,减少资源浪费。

3D打印技术辅助髂腹股沟两窗切口治疗髋臼骨折的研究

目的探讨3D打印技术辅助髂腹股沟两窗切口治疗髋臼骨折的临床效果。方法将40例髋臼骨折患者随机分为2组:对照组20例给予标准的三窗切开复位内固定治疗,观察组20例给予3D打印配合髂腹股沟两窗切口治疗。观察2组手术时间、术中出血量、X射线透视次数、术后2 d的Matta X射线评分、术后3个月d`Aubigne Postel功能评分和随访异位骨化率。结果观察组手术时间、术中出血量、X射线透视次数、异位骨化率均较对照组显著降低(P均<0.05);术后2 d Matta X射线评分优良率、术后3个月d`Aubigne Postel功能评分依良率均高于对照组(P均<0.05)。结论运用3D打印技术结合髂腹股沟两窗微创切口技术为髋臼骨折制定个性化、最优化的手术方案,具有直观、准确、可重复、通用性的优点,能够为临床手术提供指导。