Machine acceleration time series prediction for dimensional accuracy of 3D printed parts

This study explores the influence of infill patterns on machine acceleration prediction in the realm of three-dimensional(3D)printing,particularly focusing on extrusion technology.Our primary objective was to develop a long short-term memory(LSTM)network capable of assessing this impact.We conducted an extensive analysis involving 12 distinct infill patterns,collecting time-series data to examine their effects on the acceleration of the printer’s bed.The LSTM network was trained using acceleration data from the adaptive cubic infill pattern,while the Archimedean chords infill pattern provided data for evaluating the network’s prediction accuracy.This involved utilizing offline time-series acceleration data as the training and testing datasets for the LSTM model.Specifically,the LSTM model was devised to predict the acceleration of a fused deposition modeling(FDM)printer using data from the adaptive cubic infill pattern.Rigorous testing yielded a root mean square error(RMSE)of 0.007144,reflecting the model’s precision.Further refinement and testing of the LSTM model were conducted using acceleration data from the Archimedean chords infill pattern,resulting in an RMSE of 0.007328.Notably,the developed LSTM model demonstrated superior performance compared to an optimized recurrent neural network(RNN)in predicting machine acceleration data.The empirical findings highlight that the adaptive cubic infill pattern considerably influences the dimensional accuracy of parts printed using FDM technology.

Integrating Biodegradable 3-Dimensional-Printing into Tracheal Reconstruction

Background: Currently, there is no set standard treatment for long-segment tracheomalacia and stenosis. In this study we set out to explore the potential to create a tissue engineered, biodegradable and three-dimensionally (3D) printed tracheal ring as a first step towards bioengineering a long segment tracheal replacement. Method of Approach: A 3D-Computer aided design (CAD) model was produced with multiple channels to allow for cellular growth while mimicking the native anatomy. The design was optimized to allow for printability, cellular expansion, and integration and 3D printed using a modified commercial 3D printer. Results: The cells grown in the scaffold demonstrated a similar proliferation trend compared to control. Chondrocytes within the 3D printed ring retained their phenotypic properties and did not infer any significant change in flexibility, contour and strength to the scaffold. Conclusion: The combination of living cells and a 3D modeled patient specific graft may address some of the unmet clinical needs in the field of tracheal reconstruction. This proof of concept study represents a first step towards producing a 3D printed and tissue engineered long segment tracheal replacement graft for airway surgery.

Method for visualizing the shear process of rock joints using 3D laser scanning and 3D printing techniques

This study presents a visualized approach for tracking joint surface morphology.Three-dimensional laser scanning(3DLS)and 3D printing(3DP)techniques are adopted to record progressive failure during rock joint shearing.The 3DP resin is used to create transparent specimens to reproduce the surface morphology of a natural joint precisely.The freezing method is employed to enhance the mechanical properties of the 3DP specimens to reproduce the properties of hard rock more accurately.A video camera containing a charge-coupled device(CCD)camera is utilized to record the evolution of damaged area of joint surface during the direct shear test.The optimal shooting distance and shooting angle are recommended to be 800 mm and 40?,respectively.The images captured by the CCD camera are corrected to quantitatively describe the damaged area on the joint surface.Verification indicates that this method can accurately describe the total sheared areas at different shear stages.These findings may contribute to elucidating the shear behavior of rock joints.

Impact of three dimensional printing in orthopedics

The primary objective of this article is to explore effects of latest development in the area of three dimensional(3D)printing&to assess its abilities,and further undertake helpful reporting.Here the focus is to assess ad vantages of 3D printing in orthopedics and analyze how 3D printed models help solve complex 3D orthopedics distortions.This study identified that 3D models manufactured by 3D printing models reduce medical parts de velopment cost and surgical planning time.Integrating 3D printing with orthopaedics helps in understanding the conditions of problems and achieving the operation succssfully.This technology can enable doctors/surgeons to design,produce,recreate and plan operations more accurately,carefully,and economicaly.3D models can assist specialists with a visual comprehension of the patient-particular pathology and life structures.Innovation in 3D printing initiated a scaffold for the virtual outline and execution of medical procedures.This research proposes the utilisation of 3D printers as an elective procedure for the fabrication of parts.It empowers surgeons/patients for better raining,education and research.In the future,there is a foreseeable expansion of additive manufacturing in orthopedics.

3D打印技术用于经鼻蝶窦入路垂体腺瘤切除术应用效果及对血清MMP-9和IGF-1水平的影响

目的:探究3D打印技术在经鼻蝶窦入路垂体腺瘤(PA)切除术的应用效果及对血清基质金属蛋白酶-9(MMP-9)和胰岛素样生长因子-1(IGF-1)水平的影响。方法:选取2020年5月至2022年5月秦皇岛市第一医院收治的84例PA患者,按照随机数表法将其分为观察组和对照组,每组42例。对照组行经鼻蝶窦入路垂体腺瘤切除术,观察组行经鼻蝶窦入路垂体腺瘤切除术联合应用3D打印技术,比较两组肿瘤切除效果、围术期指标、视力改善情况、MMP-9和IGF-1水平,以及鼻腔功能的鼻气道阻力(NAR)、T&T嗅觉测试评分及并发症。结果:观察组肿瘤切除效果优于对照组,差异有统计学意义(U=2.286,P<0.05);观察组手术时间、术中出血量及住院时间均少于对照组,差异有统计学意义(t=4.780、11.438、11.842,P<0.05);术后3 d、7 d时观察组血清MMP-9和IGF-1水平低于对照组,差异有统计学意义(F=7.526、4.985,P<0.05);术后1个月、3个月时观察组NAR及T&T嗅觉测试评分低于对照组,差异有统计学意义(F=6.359、8.436,P<0.05);两组视力视野改善情况及并发症发生率比较,差异无统计学意义(P>0.05)。结论:3D打印技术用于经鼻蝶窦入路垂体腺瘤切除术可提高肿瘤切除效果,优化手术操作,减少创伤,有利于减轻疼痛,改善嗅觉功能与视力视野,并能降低血清MMP-9、IGF-1水平,且安全性较高。

Application and prospective of 3D printing in rock mechanics: A review

This review aims to discuss the application and development of three-dimensional printing(3DP) technology in the field of rock mechanics and the mechanical behaviors of 3D-printed specimens on the basis of various available printing materials.This review begins with a brief description of the concepts and principles associated with 3DP, and then systematically elaborates the five major applications of 3DP technology in the field of rock mechanics, namely, the preparation of rock(including pre-flawed rock) specimens, preparation of joints, preparation of geophysical models, reconstruction of complex rock structures, and performance of bridging experimental testing and numerical simulation.Meanwhile, the mechanical performance of 3D-printed specimens created using six different printing materials, such as polymers, resin,gypsum, sand, ceramics, and rock-like geological materials, is reviewed in detail.Subsequently, some improvements that can make these 3D-printed specimens close to natural rocks and some limitations of 3DP technology in the application of rock mechanics are discussed.Some prospects that are required to be investigated in the future are also proposed.Finally, a brief summary is presented.This review suggests that 3DP technology, especially when integrated with other advanced technologies, such as computed tomography scanning and 3D scanning, has great potential in rock mechanics field.

两种3D打印导板在下颌角成形术中的适应证及应用效果研究

目的分析不同数字化设计及3D打印导板在下颌角成形术中的应用效果。方法选取贵州医科大学附属口腔医院2022年1月至2023年1月收治的12例下颌角肥大患者作为研究对象。所有患者术前均行颅面部CT扫描用于三维模型重建,参考面部协调性及美观需求设计个性化下颌角截骨范围。所有患者均以下颌骨保留部分设计升支固定式截骨导板,以下颌角截除部分设计下颌下缘固定式截骨导板,术中根据不同3D打印导板使用情况分为升支固定组(组1)及下颌下缘固定组(组2)。比较两组患者术前术后下颌角形态变化。术后2周行颅面部CT扫描,重叠配准患者虚拟手术设计与手术后颅面部CT数据,测量手术设计与术后下颌角的偏差。结果所有患者均顺利完成下颌角截骨成形手术,患者对术后面型满意。组1患者术前下颌角均为外展型,组2患者中1例下颌角为外展型,其余患者下颌角为内卷型。所有患者术后下颌角角度显著高于术前(P<0.01),术后左、右侧下颌角角度对比差异无统计学意义(均P>0.05)。两组患者手术设计与术后下颌下缘之间前部、中部、后部偏差水平对比差异无统计学意义(均P>0.05)。结论数字化设计及3D打印导板引导下颌角截骨成形术具有较高的精确性,可获得良好的美容效果;升支固定式截骨导板适用于下颌角外展型患者,下颌下缘固定式截骨导板更适合下颌角内卷型患者。

Effect of gel time of 3D sand printing binder system on quality of sand mold/core

Two important factors affecting the performance of sand mold/core generated by 3D printing(3DP)are strength and dimensional accuracy,which are not only closely related to the reactivity of furan resin and the phase transition of silica sand,but also the curing agent system of furan resin.This paper studies the influence of gel time on the strength and dimensional accuracy of a 3DP sand mold/core,taking the furan resin system as an example and using a sand specimen generated by a 3DP inkjet molding machine.The experiment demonstrates that the gel time of 3 to 6 min for the sand mixture suits 3DP core-making most under the experimental condition.However,it should be noted that under the same resin condition,the strength of a no-bake sand mold/core is higher than that of a 3DP sand mold/core.The dimensional accuracy of the sand mold/core does not change significantly when the gel time is less than 15 min.Improving the activity of binder and developing ultra-strong acid with low corrosion shall be an effective way to improve the quality of the mold/core by 3D printing.

3D打印个体化髋臼翻修假体设计及应用

目的通过使用数字化重建和3D打印技术,设计和制造个体化的髋臼假体,以满足临床对于特殊骨缺损治疗的需求,并探讨该技术在临床应用中的意义。方法采用Mimics和3-matic软件进行数字化重建和假体设计;依据患者CT数据,进行数据处理和重建,设计个体化的髋臼假体;集合髋臼缺损的类型、骨质修复需求,使用3D打印技术将设计好的假体转化为实体模型,并进行后续加工工艺。结果假体顺利安装及组配,术中假体匹配程度达到术前规划要求,且髋臼底部无法填充部分通过植骨恢复骨量并达到支撑效果;髋臼翻修假体一次性植入达到预设位置,髋臼外展及前倾角度符合术前设计要求;术后一周拍摄X片后,确定假体位置良好。结论个体化假体的应用为临床医学提供了一种新的方式,可满足特殊骨缺损患者的治疗需求,对于改善医疗实践、推动医学技术的发展具有重要意义。

三维打印机ZPrinter310系统Z向升降台的结构设计

经对美国Z-Corp公司Zprinter310系统的分析和研究,根据三维打印机操作要求和特点,主要对传动系统功能部件及螺杆等主要部件进行了分析和设计,设计出了三维打印机ZPrinter310系统的Z向升降台装置,并对其他部件的设计计算提出了见解,从而为此种三维打印机的国产化设计研究打下了良好基础。

3D打印辅助体外预开窗技术在复杂主动脉疾病腔内治疗的应用

目的探讨3D打印辅助体外预开窗技术在复杂主动脉疾病腔内治疗中的临床应用价值。方法回顾性分析2020年9月至2021年11月江阴市人民医院收治的10例复杂主动脉疾病患者临床资料。患者术前根据CTA影像制作3D打印模型,辅助体外定位预开窗位置,并结合支架束径技术完成腔内修复手术。结果患者均定位精准并顺利完成手术,无中转开胸和死亡病例。自制支架时间(56.00±12.20)min,手术时长(246.80±47.43)min,血管腔内操作时间(84.80±9.62)min,植入支架(3.80±1.03)个。患者术后无感染、出血、肝肾功能异常等并发症。术后随访8个月,1例患者失访,其余9例患者支架位置良好,分支通畅,病变重塑良好,无内漏。结论应用3D打印辅助体外预开窗支架可以精准定位,对复杂主动脉疾病患者的手术安全有效,术后恢复快、并发症低,患者临床获益更佳。

3D打印技术在先天性心脏病诊疗中的应用现状

近年来新兴的3D打印技术(也称为快速成型或增材制造技术),可利用各种材料如金属、塑料,陶瓷等,将数字文件转化为物理模型。3D打印技术高度适用于先天性心脏病的诊疗,根据CT、磁共振成像、超声心动图等影像学数据制造心脏模型,可以直观地重现心脏及大血管的复杂解剖与位置关系,有助于医师更好地理解解剖结构,协助临床诊断、指导制定治疗策略。该技术已广泛应用于多种先天性心脏病的诊断、术前计划和模拟。在医学教育、促进医患沟通、介入操作培训、封堵器测试等方面亦取得良好进展。本文就3D打印技术在先天性心脏病中的应用情况做一综述。

3D打印技术在指导经导管二尖瓣介入手术中的应用与展望

二尖瓣疾病是危害人类心血管健康的常见瓣膜病之一。当前,已开发多种介入术式来治疗二尖瓣疾病。由于二尖瓣复合体特殊的解剖结构,导致介入手术难度增大,围术期并发症发生率居高不下。随着心血管3D打印技术的不断发展,3D可打印材料的更新和多学科协作相结合,3D打印成为经导管二尖瓣介入治疗中促进创新、提升手术成功率的技术。目前,患者特定的3D打印模型已用于经导管二尖瓣介入术前的器械尺寸调整、手术并发症的模拟预测等。通过运用二尖瓣介入模拟器模拟测试和多材料打印的创新方法,可以更好地预测器械将如何与患者特定的二尖瓣解剖结构相互作用。本文通过举例,阐述了3D打印在经导管二尖瓣介入治疗中的应用以及未来的发展方向。

3D打印导航模板在辅助寰枢椎椎弓根螺钉置入中的应用价值

目的:探讨三维(3D)打印导航模板辅助寰枢椎椎弓根螺钉置钉的价值。方法:回顾性分析2013年1月~2015年10月我院收治的43例寰枢椎骨折和/或脱位患者,均行后路寰枢椎切开复位内固定术。按手术方式不同分为3D打印导航模板组(19例)和传统置钉组(24例)。3D打印导航模板组术前将患者的颈椎CT数据导入Mimics 17.0软件,行3D重建并设计带钉道的导航模板后打印、消毒;术中将导航模板与置钉椎体贴合紧密后,通过定位孔钻孔、置钉。传统置钉组在C型臂X线机透视下徒手置钉。统计并对比两种置钉方法的准确率,通过测量并比较术前预设钉道角度与术后实际钉道角度差异评估进针角度的精确性。比较两组的置钉时间、手术时间、透视次数、术中出血量及患者颈肩部疼痛视觉模拟评分(visual analogue scale,VAS)和日本骨科协会(Japanese Orthopaedic Association,JOA)颈椎神经功能评分的差异情况。结果:两组患者在性别、年龄、临床诊断、病变节段、合并症及术前是否牵引复位方面均无统计学差异(P>0.05)。19例3D打印导航模板辅助置入椎弓根螺钉68枚,置钉准确率94.1%,置钉时间2.2±0.4min/枚,透视次数4.6±1.1次,手术时间197±41min,术中出血量395±64ml;传统徒手置钉组置入椎弓根螺钉76枚,置钉准确率76.3%,置钉时间3.4±0.7min/枚,透视次数9.4±2.7次,手术时间245±67min,术中出血量552±79ml。两组置钉准确率、置钉时间、透视次数、手术时间及术中出血量均有统计学差异(P<0.05)。3D打印导航模板组的内倾角及头倾角与预设值无统计学差异0.05),置钉角度的精确性明显优于徒手置钉组(P<0.05)。术后3d、6个月及12个月患者颈肩部VAS及颈椎JOA评分较术前明显好转(P<0.05),而术后6个月及12个月两组间颈肩部VAS及颈椎JOA评分无统计学差异(P>0.05)。结论:3D打印导航模板辅助寰枢椎椎弓根置钉可提高置钉准确率,同时还可缩短置钉时间、手术时间,减少透视次数和术中出血量。

骨科个体化治疗与3D打印技术

个体化治疗是骨科发展的一个重要方向,无论是个体化假体的应用还是常规假体的个体化植入,理论上均可改善骨关节假体与邻近骨性结构的匹配,从而改善病患功能状态。个体化治疗理论上的优越性无法代偿其在术前规划、设计、制造等方面程序上复杂及时限上滞后的缺陷,因而,个体化治疗常常停留在一种曲高和寡的概念。伴随图像技术的发展及3D打印技术的成熟,个体化设计及制造的生产效率有望显著提高,从而弥补传统个体化治疗效率上的不足,将个体化从概念落地为治疗理念。

精准微创根管治疗——3D导板指引下的钙化根管疏通术

目的:研究3D导板指引下采用精准微创的方法,疏通钙化根管治疗根尖周炎的临床新技术。方法:针对根管不通的前牙患者拍摄CBCT,收集CBCT数据并结合口内三维扫描数据,三维重建确定牙根方向,精确定位根管的长度及方向。进行3D导板的设计并打印,超声工作尖在3D导板的指引下去除根管内钙化物质,疏通根管,镍钛根管预备、超声冲洗结合热牙胶充填进行根管治疗。结果:使用3D导板引导,钙化根管得以精准疏通,X线检查显示疏通根管沿固有根管方向走行,根管壁破坏小,根管治疗得以顺利实施。结论:CBCT测量结合3D打印导板可以安全精准的定位根管方向和深度,微创进行根管治疗,对于钙化根管治疗具有较好的指导性。

计算机辅助设计与3D打印导板在下颌角成形术中的应用

目的介绍并探讨计算机辅助设计(CAD)与3D打印技术在下颌角成形术中的应用价值,以期优化手术模式与获得最佳整形美容效果。方法对来自四川大学华西口腔医院颌面外科与华中科技大学同济医院口腔科就诊的16例方脸患者术前拍摄头颅CBCT并进行三维数据重建,通过计算机辅助设计确定个性化下颌角截骨范围,用3D打印技术制作下颌骨模型,并制作实施准确手术的导板。在手术中用此导板引导进行下颌骨的"V-line"弧线截骨,部分患者同时结合颧骨颧弓与颏部的面部轮廓整形手术,术后效果通过3D曲线函数来评估。结果所有患者术后均对自己面型满意,术后下颌骨两侧几乎完全对称,X线显示截骨线流畅平滑,完全达到术前设计要求。结论计算机辅助设计与3D打印技术的有机结合为下颌角成形术的准确性、安全性与可预见性提供了新策略与新方法。数字化下颌角成形术的应用不仅提高了美容效果,而且能减少手术时间,降低手术难度并降低损伤重要神经血管的风险,值得临床推广应用。

3D打印模型辅助CBL教学法在骨科临床教学中的应用

目的探讨3D打印模型辅助CBL教学法在骨科临床教学中的应用和效果。方法从教学效果问卷调查与教学内容测试考核两方面,评估3D打印模型辅助CBL教学法在骨科临床教学中的应用效果,并与床边带教教学法比较。结果3D打印模型辅助CBL教学法组学生在教学吸引力、知识掌握程度、临床思维能力、技能操作能力和临床沟通能力评分高于床边带教教学法组(P<0.05)。3D打印模型辅助CBL教学法组学生在病史采集和查体,影像学资料分析,骨折描述与分型,诊断,治疗方案的评分高于床边带教教学法组(P<0.05)。结论3D打印模型辅助CBL教学法提高了学生的学习兴趣和临床综合能力,提升了学生对知识掌握的广度和深度。

3D打印技术在医学领域的应用与展望

首先简单介绍了自生物制造概念提出以来,3D打印技术在医学领域的应用已取得的进展;然后总结和重点介绍了3D打印技术在构建医学模型、人工骨骼,制造生物器官、牙齿、可控释放药物以及整形美容等方面的应用;最后对3D打印技术在医学领域的发展趋势进行了预测。

3-D打印技术用于钛网修复全上颌骨缺损6例报道

目的：探讨基于3-D打印技术制备的个体化钛网在修复全上颌骨缺损中的应用效果。方法：对6例因上颌骨肿瘤拟进行上颌骨全切除的患者。根据术前CT扫描数据．应用镜像和反求及快速成型技术，3-D打印出患侧上颌骨的树脂模型：在此模型上对钛网进行塑形，制备出个体化钛网。采用Weber—Fergusson切口和上颌牙龈缘切口进行上颌骨全切除后．将个体化钛网植入缺损区．严密缝合面部和牙龈伤口。通过临床和CT检查，评价其颌面部外形与功能、眼球突度和眼眶容积的恢复情况及并发症情况。采用SPSS17．0软件包对数据进行t检验。结果：所有病例手术顺利．预弯的钛网不需要术中再次塑形和修剪．植入的钛网与缺损周边骨床贴合紧密。术后随访4～12个月，经临床和CT检查未见肿瘤复发。颌面部外形恢复良好．两侧对称；无眼球内陷和复视，患侧眼眶容积和眼球突度与健侧相近．无显著差异（P〉0．05）；2例开口轻度受限，1例上颌牙槽突部钛网小部分外露，均为术后放疗患者。结论：应用3-D打印技术预成型的钛网适用于全上颌骨缺损的修复，能精确恢复眼眶的解剖形态和容积。