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Introduction: Three-dimensional printing is one of the technologies that promote change at an economic and social level, and one of the fundamental elements of industry 4.0. It has enormous potential for the future of medicine, establishing itself as a new paradigm. Despite its advantages, its use in our environment is incipient. Objective: To design and develop solutions based on three-dimensional technologies for the teaching and practice of biomedical sciences. Materials and methods: A technological development investigation was carried out between the Center for Assisted and Sustainable Manufacturing of the University of Matanzas and Matanzas University of Medical Sciences, between September 2019 and July 2022. The designs and fabrications were made from the acquisition of computed tomography images, or from a surface scanner, which were then processed, converted into Standard Tessellation Language format, printed, and post-processed. Virtual designs were developed using computer-aided design software. Results: Various solutions were developed including prototypes: biomodels for craniosynostosis repair and anatomical figures, custom cranial prosthesis mold, hand prosthesis, O2 line splitters, tissue scaffolds, syringe gun, face shields, breast prosthesis; autologous restoration mold and tissue expander. Conclusions: In all areas of application of this technology in medicine―except the printing of medicines, in the current context―, it is feasible to obtain solutions in the territory of Matanzas. It is therefore imperative that managers and the medical community in general, begin to acquire awareness, knowledge, and experience to ensure the optimal use of this technology.
Introducción: La impresión tridimensional es una de las tecnologías que promueve el cambio a nivel económico y social, y uno de los elementos fundamentales de la industria 4.0. Asimismo, constituye un enorme potencial para el futuro de la medicina, estableciéndose como un nuevo paradigma. A pesar de sus ventajas, su explotación en nuestro medio es incipiente. Objetivos: Diseñar y desarrollar soluciones basadas en tecnologías tridimensionales para la enseñanza y la práctica de las ciencias biomédicas. Materiales y métodos: Se realizó una investigación colaborativa, de desarrollo tecnológico entre el Centro de Fabricación Asistida y Sostenible de la Universidad de Matanzas y la Universidad de Ciencias Médicas de Matanzas, entre septiembre de 2019 y julio de 2022. Los diseños y fabricaciones se realizaron a partir de la adquisición de imágenes de tomografía computarizada, o desde un escáner de superficie, las que luego se procesaron, se convirtieron en formato Standard Tessellation Language, se imprimieron y posprocesaron. Los diseños virtuales se desarrollaron empleando un software de diseño asistido por computadora. Resultados: Se desarrollaron varias soluciones que incluyen varios prototipos: biomodelos para reparación de craneosinostosis y figuras anatómicas, molde de prótesis craneal personalizada, prótesis de mano, divisores de líneas de O2, andamios tisulares, pistola portajeringas, protectores faciales, prótesis de mama, molde para restauración autóloga y expansor tisular. Conclusiones: En todas las áreas de aplicación de esta tecnología en medicina―salvo en la impresión de medicamentos, en el contexto actual―, es factible obtener soluciones en el territorio de Matanzas. Es un imperativo, pues, que directivos y la comunidad médica en general, comiencen a adquirir conciencia, conocimientos y experiencias para garantizar la utilización óptima de esta tecnología.
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Las enfermedades raras son aquellas que tienen baja prevalencia y que, por lo tanto, el desarrollo de medicamentos para tratarlas no es rentable para las empresas farmacéuticas debido a la baja demanda. A pesar de que ya se cuenta con diferentes políticas públicas alrededor del mundo para incentivar a las industrias farmacéuticas a investigar estos medicamentos, conocidos como medicamentos huérfanos, su desarrollo conlleva muchas dificultades en las evaluaciones clínicas y el precio final para el público es muy elevado. Si bien en años recientes se ha planteado el uso de tecnología de impresión en 3D para producir estos medicamentos o incluso recurrir a otros medicamentos previamente aprobados para tratar enfermedades raras, existe un historial de mal uso de las legislaciones por parte de las empresas con el fin de generar beneficios comerciales, por lo que estas políticas deben reforzarse para que cumplan su propósito; ayudar a una población muy vulnerable. El objetivo del presente texto es exponer los resultados de una revisión documental sobre el panorama científico y sociopolítico en el que se encuentra el problema de las enfermedades raras y los medicamentos huérfanos, así como las posibles soluciones que se están desplegando para abordarlo. Deriva de un estudio que se desarrolla en el momento actual en la Universidad Autónoma Metropolitana, de Ciudad de México.
The strange illnesses are those that have low prevalence and that, therefore, the development of medications to treat them is not profitable for the pharmaceutical companies due to the drop demands. Although it is already counted with different political public around the world to motivate to the pharmaceutical industries to investigate these medications, well-known as orphan medications, their development bears many difficulties in the clinical evaluations and the final price for the public it is very high. Although in recent years he/she has thought about the use of impression technology in 3D to produce these medications or even to appeal to other medications previously approved to treat strange illnesses, a record of wrong use of the legislations exists on the part of the companies with the purpose of generating commercial benefits, for what these politicians should be reinforced so that they complete its purpose; to help a very vulnerable population. The objective of the present text is to expose the results of a documental revision on the scientific and sociopolitical panorama in which is the problem of the strange illnesses and the orphan medications, as well as the possible solutions that they are spreading to approach it. It derives of a study that is developed in the current moment in the Metropolitan Autonomous University, of Mexico City.
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Objective:To investigate the efficacy of 3D-printed quantitative bone implants assisting second-stage Masquelet technique for the treatment of long-segment bone defect following Gustilo type IIIB and IIIC tibial fractures.Methods:A retrospective case series analysis was made on 26 patients with long-segment bone defect following Gustilo type IIIB and IIIC tibial fractures treated in Wuxi Ninth People′s Hospital from July 2015 to December 2020, including 20 males and 6 females; aged 19-63 years [(46.5±4.5)years]. Gustilo classification was type IIIB in 23 patients and type IIIC in 3. In the first stage, all patients had thoroughly emergent debridement, removal of all free bone pieces, restoration of the length and force line plus externally fixion, and vacuum sealing drainage (VSD) of the residual wound. After 2-7 days, the external fixation was removed and replaced by internal fixation, with the bone cement filling in the defect area and the free flap covering the wound. The length of tibial bone defect was 5-14 cm [(6.3±0.4)cm], and the tibial defect volume was 12.2-73.1 cm 3 [(33.6±9.2)cm 3]. In the second stage (6-19 weeks after injury), the bone cement was removed, followed by autologous bone grafting. Prior to bone grafting, digital technology was used to accurately calculate the bone defect volume, and an equal volume of bone harvesting area was designe to produce the 3D printed osteotomy template. Bone grafting was conducted after bone removal according to the osteotomy template during operation. The success rate of one-time iliac bone extraction, bone harvesting time, and bleeding volume were recorded. Pain in the bone extraction area was evaluated by visual analogue score (VAS) at 1 day and 1 month after operation and at the last follow-up. Wound healing, complications, and bone healing were observed. Life quality was evaluated by health survey brief form (SF-36) including scores of physical component summary (PCS) and mental component summary (MCS) before bone grafting and at the last follow-up. Results:All the patients were followed up for 13-53 months [(32.3±12.5)months]. One-time iliac bone extraction was successful in all the patients. Bone harvesting time was 15-30 minutes [(21.0±2.5)minutes]. The bleeding volume was 50-120 ml [(62.3±29.0)ml]. The VAS was 1-4 points [(1.2±0.9)points] at 1 day after operation, higher than these (0.0±0.0)points at 1 month after operation and at the last follow-up (all P<0.01). Totally, 25 patients obtained wound healing after operation, except for 1 patient with superficial wound infection after bone grafting that was healed by dressing change. There was 1 patient with bone infection after 3 months of bone grafting that was healed by repeated surgery with Masquelet technique in the first and second stage. Besides, 2 patients had symptoms of cutaneous nerve injury in the iliac donor area. The time of bone healing was 4-7 months [(5.8±0.8)months]. The scores of PCS and MCS in SF-36 at the last follow-up were (73.6±12.8)points and (83.6±13.2)points, significantly higher than those before bone grafting [(46.8±0.5)points, (60.7±2.0)points] (all P<0.01). Conclusion:Second-stage Masquelet technique with 3D printed quantitative bone implants for the treatment of long-segment bone defect following Gustilo type IIIB and IIIC tibial fractures is associated with shortened bone harvesting time, attenuated pain, reduced complications, accelerated bone healing and improved function.
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OBJECTIVE@#To explore the effectiveness of a new point contact pedicle navigation template (referred to as "new navigation template" for simplicity) in assisting screw implantation in scoliosis correction surgery.@*METHODS@#Twenty-five patients with scoliosis, who met the selection criteria between February 2020 and February 2023, were selected as the trial group. During the scoliosis correction surgery, the three-dimensional printed new navigation template was used to assist in screw implantation. Fifty patients who had undergone screw implantation with traditional free-hand implantation technique between February 2019 and February 2023 were matched according to the inclusion and exclusion criteria as the control group. There was no significant difference between the two groups ( P>0.05) in terms of gender, age, disease duration, Cobb angle on the coronal plane of the main curve, Cobb angle at the Bending position of the main curve, the position of the apical vertebrae of the main curve, and the number of vertebrae with the pedicle diameter lower than 50%/75% of the national average, and the number of patients whose apical vertebrae rotation exceeded 40°. The number of fused vertebrae, the number of pedicle screws, the time of pedicle screw implantation, implant bleeding, fluoroscopy frequency, and manual diversion frequency were compared between the two groups. The occurrence of implant complications was observed. Based on the X-ray films at 2 weeks after operation, the pedicle screw grading was recorded, the accuracy of the implant and the main curvature correction rate were calculated.@*RESULTS@#Both groups successfully completed the surgeries. Among them, the trial group implanted 267 screws and fused 177 vertebrae; the control group implanted 523 screws and fused 358 vertebrae. There was no significant difference between the two groups ( P>0.05) in terms of the number of fused vertebrae, the number of pedicle screws, the pedicle screw grading and accuracy, and the main curvature correction rate. However, the time of pedicle screw implantation, implant bleeding, fluoroscopy frequency, and manual diversion frequency were significantly lower in trial group than in control group ( P<0.05). There was no complications related to screws implantation during or after operation in the two groups.@*CONCLUSION@#The new navigation template is suitable for all kinds of deformed vertebral lamina and articular process, which not only improves the accuracy of screw implantation, but also reduces the difficulty of operation, shortens the operation time, and reduces intraoperative bleeding.
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Humans , Orthopedic Procedures , Pedicle Screws , Retrospective Studies , Scoliosis/surgery , Spinal Fusion/methods , Spine , Surgery, Computer-Assisted/methodsABSTRACT
The interventional therapy of vascular stent implantation is a popular treatment method for cardiovascular stenosis and blockage. However, traditional stent manufacturing methods such as laser cutting are complex and cannot easily manufacture complex structures such as bifurcated stents, while three-dimensional (3D) printing technology provides a new method for manufacturing stents with complex structure and personalized designs. In this paper, a cardiovascular stent was designed, and printed using selective laser melting technology and 316L stainless steel powder of 0-10 µm size. Electrolytic polishing was performed to improve the surface quality of the printed vascular stent, and the expansion behavior of the polished stent was assessed by balloon inflation. The results showed that the newly designed cardiovascular stent could be manufactured by 3D printing technology. Electrolytic polishing removed the attached powder and reduced the surface roughness Ra from 1.36 µm to 0.82 µm. The axial shortening rate of the polished bracket was 4.23% when the outside diameter was expanded from 2.42 mm to 3.63 mm under the pressure of the balloon, and the radial rebound rate was 2.48% after unloading. The radial force of polished stent was 8.32 N. The 3D printed vascular stent can remove the surface powder through electrolytic polishing to improve the surface quality, and show good dilatation performance and radial support performance, which provides a reference for the practical application of 3D printed vascular stent.
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Humans , Stainless Steel , Powders , Cardiovascular System , Constriction, PathologicABSTRACT
As imaging technology develops rapidly, dynamic and static guided technology is widely used in many medical fields now. In order to improve the success rate, reduce surgical complications and improve future prognosis, domestic and foreign experts have introduced digital navigation technology into apical surgery. With the help of digital navigation technology, apical lesions can be easily located and the scope of osteotomy can be limited, which can make the surgery be completed accurately, especially in complex clinical cases. This study overviews the clinical use and research progress of dynamic and static guided technology in apical surgery, summarizes the advantages and disadvantages of this technique as well as looks forward to its future.
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Technology , Endodontics , Diagnostic ImagingABSTRACT
【Objective】 To investigate the application value of three-dimensional printed guiding device in sacral neuromodulation in children. 【Methods】 A total of 17 patients admitted during Jan.2017 and Nov.2022 were divided into two groups: control group (n=8), using traditional method to locate sacral foramen for puncture; three-dimensional printed guiding device group (n=5), using three-dimensional printing technology to make individual guiding device for puncture. The clinical indexes of the two groups were evaluated, including puncture time, puncture numbers, intraoperative X-ray exposure times, postoperative evaluation time and second-stage conversion rate. The evaluation indexes of postoperative complications were wound bleeding, wound infection, wound rupture, electrode fracture, displacement or prolapse. 【Results】 In the control group, 1 case was diagnosed as bladder-bowel dysfunction, the remaining 7 were neurogenic bladder; in the three-dimensional printed guiding device group, all 9 cases were diagnosed as neurogenic bladder. The puncture time was shorter in the three-dimensional printed guiding device group than in the control group [85(70-90) min vs.138(133-208) min], the puncture numbers were fewer [15(12-20) vs.22(18-26)], and the X-ray exposure times were fewer [12(12-17) vs.19(16-23)] (all P<0.05). The initial stimulation voltage, postoperative evaluation time and second-stage conversion rate were not statistically significant. 【Conclusion】 Compared with the traditional method, the use of three-dimensional printed guiding device can reduce the puncture numbers and shorten the puncture time in the process of sacral neuromodulation in children.
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@#Objective To investigate the surgical strategies and clinical efficacy of transmitral septal myectomy in the treatment of recurrent left ventricular outflow tract obstruction (LVOTO) after alcohol septal ablation. Methods The clinical data of patients with recurrent LVOTO after alcohol septal ablation from July 2020 to July 2021 in the Department of Cardiac Surgery, Guangdong Provincial People's Hospital were retrospectively analyzed. Patients were preoperatively evaluated by echocardiography, cardiac magnetic resonance imaging, cardiac computed tomography, 3D modeling and printing technology. A personalized surgical strategy was preoperatively developed according to multimodality imaging assessment, while visual exploration was performed on the digital model and simulated surgical resection was performed on the printed model. Results Two female patients were enrolled, aged 62 years and 64 years, respectively. Totally endoscopic transmitral extended myectomy was successfully performed on both patients with aortic cross-clamping time of 96 min and 85 min, respectively. LVOTO was relieved immediately (subaortic peak pressure gradient decreased from 100 mm Hg to 4 mm Hg and from 84 mm Hg to 6 mm Hg, respectively) and the mitral regurgitation significantly improved after the procedure. No patient had complete atrioventricular block or required permanent pacemaker implantation. The patients were discharged uneventfully without postoperative complications. Conclusion Personalized totally endoscopic transmitral extended myectomy combined with multimodality imaging assessment and 3D modeling and printing has an acceptable clinical effect in patients with recurrent LVOTO after alcohol septal ablation. The procedure can precisely resect the hypertrophic septal myocardium while avoiding serious complications such as septal perforation or complete atrioventricular block.
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Currently three dimensional bio-printing technology has become one of the hot topics for tissue engineering tracheal grafting.Different biomaterials have their own performance advantages in the preparation and regeneration of tracheal scaffolds.It is particularly imperative to seek natural or polymeric materials with excellent profiles of printability, structural stability and biocompatibility to enable neo-cartilage formation, neo-epithelialization and neo-vascularization of tissue engineering trachea grafting.This review summarized the shortcomings and challenges of classifying and applying materials for three dimensional bio-printing tissue engineering trachea, aiming to provide new rationales for researches and applications of tissue engineering tracheal grafting.
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La Impresión 3D es una tecnología emergente utilizada cada vez más en medicina. En los países en vías de desarrollo, donde las fracturas por motocicletas y automóviles se encuentran en aumento, la disponibilidad de fijadores externos para el manejo de fracturas abiertas es un problema frecuente. La impresión 3D puede ser una alternativa económica e igualmente confiable a los dispositivos tradicionales elaborados con acero o titanio. El objetivo de este trabajo es mostrar la experiencia con el uso de Impresión 3D y su aplicación en el manejo clínico de fracturas abiertas diafisiarias de tibia. Se realizó un estudio pre-experimental y prospectivo. Se incluyeron 14 pacientes con fracturas de tibia AO/ASIF 42A, 42B y 42C tratados con un fijador externo con rótulas elaboradas con Impresión 3D como medida de Control de Daños en Ortopedia desde su ingreso hasta su resolución definitiva. Todos los pacientes fueron de sexo masculino, con un promedio de edad 23,16 años con 50% entre 20-23 años. Las fracturas fueron 42,85% tipo 42A, 37,71% 42B y 21,42% 42C. El 78,57% de las fracturas fueron ocasionadas por motocicletas: 57,14% grado II según Gustilo y Anderson, un 28,57% grado III y 14,28% grado I. El 37,71% eran politraumatizados. Ninguno de los pacientes presentó complicaciones como pérdida de la reducción, aflojamiento de las rótulas, ruptura o fatiga de las rótulas ni fatiga de la barra. La impresión 3D demostró ser una herramienta y alternativa útil en el manejo agudo de fracturas abiertas diafisiarias de tibia(AU)
3D Printing is an emerging technology used more and more in medicine. In developing countries, where motorcycle and automobile fractures are on the rise, the availability of external fixators for the management of open fractures is a frequent problem. 3D printing can be a cheap and equally reliable alternative to traditional devices made of steel or titanium. The objective of this work is to show the experience with the use of 3D Printing and its application in the clinical management of open diaphyseal fractures of the tibia. A pre-experimental and prospective study was made. 14 patients with AO/ASIF tibia fractures 42A, 42B and 42C treated with an external fixator with 3D-printed ball-caps as a Damage Control measure in Orthopedics from admission to final resolution were included. All patients were male, with an average age of 23,16 years, 50% between 20-23 years. The fractures were 42,85% type 42A, 37,71% 42B and 21,42% 42C. 78,57% of the fractures were caused by motorcycles: 57,14% grade II according to Gustilo and Anderson, 28,57% grade III and 14.28% grade I. 37,71% were polytraumatized. None of the patients had complications such as loss of reduction, loosening of the patellas, rupture or fatigue of the patellas, or rod fatigue. 3D printing proved to be a useful tool and alternative in the acute management of open diaphyseal fractures of the tibia(AU)
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Humans , Male , Female , Adolescent , Fractures, Open , Accidents, Traffic , Medical Records , Data CollectionABSTRACT
Pelvic and acetabular fractures are one of the serious traumatic diseases, leading to a high rate of disability and fatality. Their operative principles are anatomical repositioning and rigid fixation to achieve early functional exercise and avoid complications. The updating modern technology has made precision and minimally invasion a trend in orthopedic surgery. An increasingly number of new technologies has been applied in clinical surgery, such as three-dimensional printing, three-dimensional navigation, and orthopedic robotics, each with its own characteristics. Of them, three-dimensional printing technology is more advantageous in terms of reducing surgical cost and risk, enhancing surgical efficiency, achieving surgical precision and reducing radiation exposure, as evidenced by a large number of clinical case reports and randomized controlled trials. This paper summarizes the current situation and assesses the prospects of three-dimensional printing technology in the diagnosis and treatment of pelvic and acetabular fractures in order to provide reference for orthopedic colleagues.
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Objective:To explore the feasibility and accuracy of three-dimensional (3D) modeling methods based on ultrasound imaging data for normal and abnormal fetal cardiac structures, and to construct a methodology system for 3D printing of fetal heart based on ultrasound.Methods:A total of 93 fetuses examined in Tangdu Hospital of Air Force Military Medical University from January to December 2019 were selected. Fetal echocardiography was obtained using spatio-temporal image correlation (STIC). Ninety-three hearts were 3D modeled by blood flow modeling, blood pool modeling and cavity modeling, and printed by stereolithography technique. The data measured on the 3D digital models and 3D printed solid models were compared with the corresponding fetal echocardiographic images respectively in order to evaluate the accuracy of the modeling methods.Results:The fetal cardiac blood flow models based on Doppler flow image data showed the malformation and trend of small blood vessels. The fetal cardiac structure models printed based on blood pool modeling displayed the malformation of heart and large blood vessels. Models printed based on cavity modeling method accurately displayed valve and structural defects.For 83 normal fetal hearts, the long diameters of left and right ventricles measured on echocardiography [(15.3±1.9)mm, (13.2±1.9)mm] were compared with those measured on digital models [(15.1±1.9)mm, (12.9±1.9)mm] and 3D printed models[(15.1±1.9)mm, (13.0±1.9)mm], respectively, and there were no significant differences between any two groups of them ( P>0.05). Bland-Altman showed good consistency for all measurements within and between operators. Conclusions:The three modeling methods, including blood flow modeling, blood pool modeling and cavity modeling, have their own advantages in displaying different types of fetal heart malformations. Appropriate modeling methods should be selected for 3D modeling and printing to make up for the limitations of single modeling method. The consistency between measurements on 3D models and those on echocardiography is high, and the repeatability between operators is good.
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Objective:To investigate the effect of ultra-low dose (ULD) computed tomography (CT) scanning on the diagnosis of ankle fractures and the quality of a three-dimensional printing (3DP) model.Methods:This study was a prospective study. A total of 61 patients with clinical ankle fractures treated conservatively in Zhuhai Hospital of Guangdong Hospital of Traditional Chinese Medicine from November 2019 to January 2022 were included in this study. Patients underwent standard dose (SD) CT scan and ultra-low dose (ULD) CT scan, respectively. The tube voltage/tube current of SD and ULD were 120 kV/100 mAs and 80 kV/10 mAs, respectively. Two senior radiologists evaluated the presence of ankle fractures. The effective radiation dose ( E), noise, signal-to-noise ratio (SNR), contrast signal-to-noise ratio (CNR), and CT value of bone cortex minus CT value of peripheral fat (CTc) were compared. The radiologists also evaluated the discoverability, diagnosability, and overall image quality of the fracture line according to Likert′s 5-point scoring method. Two senior orthopedists subjectively evaluated the quality of each 3DP model (model clarity and operation guidance). A score ≥ 3 indicated that the quality of the CT diagnostic image and 3DP model were acceptable. Results:The interval between the two CT scans was (9.23 ± 1.92) d. A total of 94 fracture sites were found. There were no missed diagnosis or misdiagnosis based on the SD and ULD scans.Noise, SNR, and CNR were better on the SD CT scanning ( F=5.92, 9.70, 8.32, P=0.00), however, CTc was higher on the ULD scans ( F=27.55, P<0.01). The image scores of the SD and ULD scans were (4.97 ± 0.18) and (4.21 ± 0.71), and the quality scores of the 3DP model (4.99 ± 0.01) and (4.87 ± 0.34), respectively. The SD scans were better than the ULD scans with respect to CT image quality and 3DP model quality ( Z=-6.88, -2.91, P<0.01), but both were considered suitable to meet clinical needs (all ≥ 3 points). The E associated with SD and ULD scannings were (34.68 ± 4.96) μSV and (1.04 ± 0.10) μSV, respectively. The latter was thus significantly better than the former ( F=38.77, P =0.00). Conclusions:The E value of ULD scanning is about 3.00% of SD scanning E, which can meet the needs of clinical diagnosis of ankle fracture and 3DP model printing diagnosis.
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Objective:To explore the short-term outcomes of reconstruction of tumorous critical bone defects at femoral shaft with a 3D printed ultra-short stem with a porous structure.Methods:From September 2016 to June 2018, 8 patients underwent reconstruction of critical bone defects with a 3D printed ultra-short stem with a porous structure after resection of femoral shaft malignant tumor at Department of Orthopaedics, West China Hospital. There were 4 males and 4 females, with an average age of 36.9 years (from 11 to 61 years). Their preoperative Enneking staging was stage Ⅱb in all. There were 3 osteosarcomas, 2 Ewing sarcomas, 2 chondrosarcomas and one periosteal osteosarcoma. Preoperative CT/MRI image fusion technology was used to define the surgical boundary, design the guide plate and prosthesis, and perform surgical simulation. Tomosynthesis-shimadzu Metal Artefact Reduction technology was used to evaluate osseointegration. Complications and bone oncology prognosis of the patients were documented. The lower limb function of the patients was evaluated using Musculoskeletal Tumor Society (MSTS) 1993 scoring and knee range of motion.Results:The overall follow-up time ranged from 36 to 50 months, averaging 42.8 months. During operation one patient sustained a periprosthesis fracture, the union of which was followed up after wire assisted fixation. There was no local tumor recurrence, lung metastasis or death. The last follow-up revealed good osseointegration and basically isometric lower extremities in all cases. There was no such a complication as aseptic loosening of the prosthesis, deep infection or prosthesis fracture during the follow-up period. At the last follow-up in the 8 patients, the flexion range of the knee joint was 116.2°±9.1°, significantly improved compared with that before operation (98.8°±10.9°), and the MSTS score was (26.2±2.1) points, also significantly improved compared with that before operation [(21.6±1.8) points] ( P<0.05). Conclusions:Reconstruction with a 3D printed ultra-short stem with a porous structure is an accurate operation for femoral shaft tumorous bone defects. With careful preoperative design, intraoperative manipulation and strict postoperative follow-up management, this operation can lead to fine early curative outcomes for long shaft critical bone defects.
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One of the challenges in developing three-dimensional printed medicines is related to their stability due to the manufacturing conditions involving high temperatures.This work proposed a new pro-tocol for preformulation studies simulating thermal processing and aging of the printed medicines,tested regarding their morphology and thermal,crystallographic,and spectroscopic profiles.Gener-ally,despite the strong drug-polymer interactions observed,the chemical stability of the model drugs was preserved under such conditions.In fact,in the metoprolol and Soluplus? composition,the drug's solubilization in the polymer produced a delay in the drug decomposition,suggesting a pro-tective effect of the matrix.Paracetamol and polyvinyl alcohol mixture,in turn,showed unmistakable signs of thermal instability and chemical decomposition,in addition to physical changes.In the presented context,establishing protocols that simulate processing and storage conditions may be decisive for obtaining stable pharmaceutical dosage forms using three-dimensional printing technology.
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A partir dos avanços da tecnologia CAD/CAM na Odontologia, observa-se a crescente utilização da manufatura aditiva na confecção de peças protéticas. Este trabalho propões a avaliação da acurácia interna e linha de cimentação de endocrowns produzidas através de manufatura aditiva e subtrativa. Para isso foi produzido um modelo mestre preparado para coroa endocrown, o qual foi posteriormente escaneado para desenho e fabricação das restaurações, segundo sua manufatura: aditiva (n=14) e subtrativa (n=14). As endocrowns tiveram sua parte interna escaneadas e através de software de inspeção foram comparadas as diferenças entre o projeto (CAD) e a restauração manufaturada, com a distribuição no interior de cada espécime de 90 pontos de aferição equidistantes. Seus respectivos valores de desvio foram utilizados para o cálculo de um valor eficaz (root mean square - RMS). Além disso, foi mensurada a desadaptação entre as endocrowns e modelo mestre, mediante a técnica da réplica de silicone digital, com aferição da linha de cimentação em pontos padronizados e distribuídos de forma equidistantes na região marginal, axial e pulpar, bem como a mensuração da linha de cimentação absoluta. Os dados da veracidade/acurácia interna passaram por teste de normalidade e comparação estatística pelo teste t student não pareado (α=0,05). Os resultados para veracidade interna RMS (Impresso 49.6032 µm ± 3.8917 e fresado 48.5554µm ± 2.2992) não demonstraram diferença estatística significante entre os grupos (p valor >0.05), entretanto sob avaliação qualitativa em gráfico de cores, houve distorções entre as peças produzidas e o projeto em software CAD, com padrões de distorção distintos segundo o tipo de manufatura. Quanto aos resultados da linha de cimentação, os valores de cada região passaram por teste de normalidade e comparação pelo teste t student não pareado (α=.05). Sem diferença estatística (p valor >0.05) na região marginal (impresso 52.9121 µm ± 10.8946 e fresado 61.8303 µm ± 13.4616) e linha de cimentação absoluta (impresso 84.642µm ± 8.0161 e fresado 89.1016µm ± 10.7006.). Contudo nos resultados da linha de cimentação em região axial (impresso 78.2094µm ± 10.5483 e fresado 95.3686µm ± 9.550), bem como região pulpar (impresso 160.9635µm ± 18.3995 e fresado 131.11µm ± 23.7442), houve diferença estatística significante entre os grupos (p < 0,05). Conclui-se, portanto, com relação aos valores gerais, tais como a linha de cimentação absoluta e veracidade interna, que não houve diferença estatística significante entre as duas manufaturas. Todavia, quanto a avaliações locais da linha de cimentação, o grupo impresso apresentou os melhores resultados em região axial, o grupo fresado em região pulpar e ambos os grupos com resultados semelhantes estatisticamente para região marginal. (AU)
Following the advances in CAD/CAM technology in dentistry and the increasing use of additive manufacturing in prosthetic dentistry, this study proposes the evaluation of the trueness and cementation line adaptation of endocrowns produced through additive and subtractive manufacturing. A master model prepared for endocrown and scanned for design and fabrication of restorations, according to their manufacture type: additive (n=14) and subtractive (n=14). The endocrowns had their internal area scanned and, through an inspection software, the differences between the design (CAD) and the manufactured restoration were compared, based by the distribution in each specimen of 90 equidistant measurement points. And their respective deviation values were used for the calculation of Root Mean Square (RMS). In addition, the misfit between the endocrowns and the master model was measured using the digital silicone replica technique, and the cementation line measured at standardized and equidistant points in marginal, axial, and pulp regions. As well as the measurement of the absolute cementation line. The trueness data underwent a normality test and statistical comparison by the unpaired student t test (α=.05). The results for RMS internal trueness (Printed 49.6032 µm ± 3.8917 and milled 48.5554 µm ± 2.2992) did not show a statistically significant difference between the groups (p value >0.05), however under qualitative evaluation in a color map, there are distortions between the crowns produced and the design in CAD software, following different patterns according to the manufacture type. As for the results of the cementation line, the data of each region underwent a normality test and comparison by the unpaired t student test (α=.05). No statistical difference (p value >0.05) in the marginal region (printed 52.9121 µm ± 10.8946 and milled 61.8303 µm ± 13.4616) and absolute cementation line (printed 84.642µm ± 8.0161 and milled 89.1016 µm ± 10.7006.) were observed. However, in the results of the cementation line at the axial region (printed 78.2094µm ± 10.5483 and milled 95.3686µm ± 9.550), as well the pulp region (printed 160.9635µm ± 18.3995 and milled 131.11µm ± 23.7442), there was a statistically significant difference between the groups (p < 0.05). This study concludes that in relation to the global values, such as the absolute cementation line and internal trueness, that there was no statistically significant difference between the two manufacturing types. However, regarding the local assessments of the cementation line, the printed group presented the best results in the axial region, the milled group in the pulp region, and both groups with statistically similar results for the marginal region. (AU)
Subject(s)
Dental Prosthesis , Computer-Aided Design , Dental Marginal Adaptation , Printing, Three-DimensionalABSTRACT
RESUMO A manufatura aditiva, mais popularmente conhecida como impressão tridimensional, baseia-se no desenvolvimento de um objeto com a ajuda de um software de desenho assistido por computador seguido de sua impressão por meio da deposição de uma matéria-prima, camada por camada, para a construção do produto desejado. Existem vários tipos de técnicas de impressão tridimensional, e o tipo de processo de impressão escolhido depende da aplicação específica do objeto a ser desenvolvido, dos materiais a serem utilizados e da resolução necessária à impressão do produto final. A impressão tridimensional abriu perspectivas na pesquisa e revolucionou o campo das ciências da saúde, com a possibilidade de criação e de desenvolvimento de produtos personalizados de maneira rápida, econômica e de forma mais centralizada do que no processo de manufatura tradicional. As tecnologias de manufatura aditiva remodelaram os diagnósticos médicos; as medidas preventivas e pré-operatórias; o tratamento e a reabilitação, assim como os processos de engenharia de tecidos nos últimos anos. Na oftalmologia, as aplicações da impressão tridimensional são extensas. Modelos anatômicos para aplicação na área da educação e planejamentos cirúrgicos, desenvolvimento de implantes, lentes, equipamentos para diagnósticos, novas aplicações terapêuticas e desenvolvimento de tecidos oculares já estão em desenvolvimento. Por possuir um campo amplo e ser alvo de pesquisa constante, a área oftalmológica permite que a manufatura aditiva ainda seja amplamente utilizada a favor dos médicos e dos pacientes.
ABSTRACT Additive manufacturing, more popularly known as three-dimensional (3D) printing, is based on the development of an object with the help of computer-aided design software followed by its printing through the deposition of a material, layer by layer, to create the desired product. There are several types of 3D printing techniques and the type of printing process chosen depends on the specific application of the object to be developed, the materials to be used, and the resolution required to print the final product. 3D printing has brought new perspectives to research and revolutionized the field of health sciences, with the possibility of creating and developing customized products in a faster, more economical, and more centralized way than in the traditional manufacturing process. Additive manufacturing technologies have reformulated medical diagnostics, preventive, preoperative, treatment, and rehabilitation, as well as tissue engineering processes in recent years. In ophthalmology, the applications of 3D printing are extensive. Anatomical models for application in education and surgical planning, development of implants, lenses, diagnostic equipment, new therapeutic applications, and development of ocular tissues (3D bioprinting) are already under development. As it has a wide field and is the subject of constant research, the ophthalmic area allows additive manufacturing to still be widely used in favor of doctors and patients.
Subject(s)
Humans , Ophthalmology , Imaging, Three-Dimensional , Printing, Three-Dimensional , Polymers , Prostheses and Implants , Biosensing Techniques , Computer-Aided Design , Recycling , Bioprinting , Stereolithography , Models, AnatomicABSTRACT
Planejamento pré-operatório de correção de deformidades supramaleolares através de impressão 3DRELATO DE CASOModelos impressos em 3D têm sido explorados profundamente no campo médico, destacando-se como importante ferramenta de auxílio para planejamento cirúrgico. Os autores apresentam relato de caso de um paciente, com artrose pós-traumática do tornozelo direito, submetido a osteotomia supramaleolar, em cunha de fechamento medial. Esta cirurgia foi realizada após planejamento operatório por impressão 3D, o que pode demonstrar reprodutibilidade deste método. (AU)
3D printed models have been explored deeply in the medical field, standing out as an important aid tool for surgical planning. The authors present a case report of a patient with post-traumatic arthrosis of the right ankle, who underwent supramaleolar osteotomy, using a medial closure wedge. This surgery was performed after operative planning by 3D printing, which can demonstrate the reproducibility of this method. (AU)
Subject(s)
Humans , Osteoarthritis , Osteotomy , Surgical Procedures, Operative , Congenital Abnormalities , Planning , Printing, Three-DimensionalABSTRACT
ABSTRACT: This study aimed to compare the trueness and precision of physical models manufactured chairside (intraoral scanner and 3D printed) or by plaster models obtained using impression with alginate or addition silicone. A full- arch stainless steel die was impressed to obtain ten physical models for each group. The models were measured in a stereomicroscope, considering four linear distances. To assess the precision accuracy, an analysis of the measurement variability was carried out, identified by the coefficients of variation and by the Levene's test to compare the groups. To analyze trueness, the data average was subtracted from the database and compared considering alpha as 5 %. Considering precision, the higher dispersion of data occurred in the models obtained with silicone impression. And for trueness, Kruskal Wallis and Dunn tests results did not indicate differences between the groups in the anteroposterior linear distances (p> 0.05). Only in anterior transverse distance obtained through TRIOS (0.31 mm), it presented lower accuracy compared to the models from silicone impression (0.13 mm); however, at transverse posterior distance, the models from silicone impression showed the lowest accuracy (p 0.05). The physical dental models obtained by digital and analog workflows showed acceptable dimensional accuracy expressed by high precision and trueness. There is no difference between the evaluated intraoral scanner systems and the impression materials for the full-arch impression.
RESUMEN: Este estudio tuvo como objetivo comparar la veracidad y precisión de modelos físicos fabricados en la clínica dental (escáner intraoral e impreso en 3D) o por modelos de yeso obtenidos mediante impresión con alginato o silicona de adición. Una matriz de acero inoxidable de arco completo fue impresa para obtener diez modelos físicos para cada grupo. Los modelos se midieron en un estereomicroscopio, considerando cuatro distancias lineales. Se realizó un análisis de la variabilidad de la medida para evaluar la precisión, identificada por los coeficientes de variación y por la prueba de Levene para comparar los grupos. Para analizar la veracidad, el promedio de los datos se restó de la base de datos y se comparó considerando alfa como 5 %. Considerando la precisión, la mayor dispersión de datos ocurrió en los modelos obtenidos con impresión de silicona. Y para la veracidad, los resultados de las pruebas de Kruskal Wallis y Dunn no indicaron diferencias entre los grupos en las distancias lineales anteroposteriores (p> 0,05). Solo en la distancia transversal anterior obtenida mediante TRIOS (0,31 mm) presentó menor precisión en comparación con los modelos de impresión de silicona (0,13 mm); sin embargo, la distancia transversal posterior, los modelos de impresión de silicona mostraron la menor precisión (p 0,05). Los modelos dentales físicos obtenidos mediante flujos de trabajo digitales y analógicos mostraron una precisión dimensional aceptable expresada por alta precisión y veracidad. No se observó diferencia entre los sistemas de escáner intraoral evaluados y los materiales de impresión para la impresión de arco completa.
ABSTRACT
RESUMEN: La reconstrucción de las paredes orbitarias fracturadas es compleja debido a la gran cantidad de parámetros volumétricos que posee. Una restitución inadecuada de ellas habitualmente está asociada a secuelas postquirúrgicas en el paciente. El contar con herramientas que optimicen la restitución de la forma anatómica de la órbita en su reconstrucción es de vital importancia, y la utilización de nuevas tecnologías ha permitido mejorar los resultados quirúrgicos, tanto anatómicos como funcionales. El objetivo de este artículo es mostrar dos herramientas quirúrgicas que permiten optimizar los resultados terapéuticos en pacientes con fractura de órbita, que son el modelo estereolitográfico con imagen en espejo y la tomografía computada intraoperatoria. Se presentan las características de estas herramientas, su utilización en tres casos de pacientes con fractura orbitaria y los resultados obtenidos en el post operatorio.
ABSTRACT: The reconstruction of fractured orbital walls is complex due to the many volumetric parameters involved. An inadequate restitution of these walls may be associated with postsurgical sequelae in the patient. Is vitally important to count with tools that optimize the restitution of the orbit's anatomic shape during its reconstruction, and the use of new technologies has allowed the improvement of the surgical results, both anatomical and functional. The aim of this article is to show two surgical tools that allow to optimize the therapeutic results in patients with orbital fracture, which are stereolithographic models with mirror image technique, and intraoperative computed tomography. Their characteristics, their use in three cases of patients with orbital fractures, and the postoperative results are shown.