Morphological Design and Study of a 3D Printed Integrated Fusion Device Based on CT Measurement Data Assisted Anterior Lumbosacral Spine / Diseño Morfológico y Estudio de un Dispositivo de Fusión Integrado Impreso en 3D Basado en Datos de Medición de TC Asistida de Columna Lumbosacra Anterior

SUMMARY: To measure and study the anatomical morphological data of the lumbar 5 to sacral 1 intervertebral space with the aid of CT and design an anatomical anterior lumbosacral 3D printed integrated interbody fusion for the treatment of degenerative lumbosacral spine diseases. 100 adults (50 of each sex) who underwent CT examination of the lumbar spine in our hospital were selected, and their lumbar 5 to sacral 1 intervertebral space anatomical data were measured, including the anterior lumbar convexity angle, different sagittal and coronal heights, and the sagittal and coronal diameters of the superior and inferior endplates. The measured data were also statistically analyzed, and morphological design and study of the 3D printed integrated fusion device in the anterior lumbosacral spine was performed by applying computer software. When comparing the coronal and sagittal diameters of the superior and inferior endplates from lumbar 5 to sacral 1, the differences were statistically greater in men than in women (P0.001). When comparing the height at different positions in the median sagittal plane, both males and females showed an anterior high and posterior low pattern. In the coronal plane, both males and females showed the highest height in the middle position (P0.001). CT can measure the anatomical data of the lumbosacral spinal hiatus more accurately. The 3D-printed anterior integrated fusion device of the lumbosacral spine designed according to the analysis of the data results is more in line with the anatomical structure of the lumbosacral spine, fits well with the superior and inferior endplates, and effectively restores the height and anterior convexity angle of the lumbosacral space.

El objetivo de este trabajo fue medir y estudiar los datos morfológicos anatómicos del espacio intervertebral lumbar 5 a sacro 1 con la ayuda de TC y diseñar una fusión intersomática integrada anatómica lumbosacra anterior impresa en 3D para el tratamiento de enfermedades degenerativas de la columna lumbosacra. Se seleccionaron en nuestro hospital 100 adultos (50 de cada sexo) que se sometieron a un examen de TC de la columna lumbar y se midieron los datos anatómicos del espacio intervertebral lumbar 5 al sacro 1, incluyendo el ángulo de la convexidad lumbar anterior, diferentes alturas sagital y coronal, y los diámetros sagital y coronal de las placas terminales superior e inferior. Los datos medidos también se analizaron estadísticamente y se realizó el diseño morfológico y el estudio del dispositivo de fusión integrado impreso en 3D en la columna lumbosacra anterior mediante la aplicación de software informático. Al comparar los diámetros coronal y sagital de las placas terminales superior e inferior desde lumbar 5 hasta sacro 1, las diferencias fueron estadísticamente mayores en hombres que en mujeres (P 0,001). Al comparar la altura en diferentes posiciones en el plano mediano, tanto hombres como mujeres mostraron un patrón anterior alto y posterior bajo. En el plano coronal, tanto hombres como mujeres mostraron la altura más alta en la posición media (P0,001). La TC puede medir los datos anatómicos del hiato espinal lumbosacro con mayor precisión. El dispositivo de fusión anterior integrado impreso en 3D de la columna lumbosacra diseñado de acuerdo con el análisis de los resultados de los datos está más en línea con la estructura anatómica de la columna lumbosacra, se adapta bien a las placas terminales superior e inferior y restaura eficazmente la altura y la parte anterior del ángulo de convexidad del espacio lumbosacro.

A prototype 3D printed suction port adapter for a wireless otoendoscope

Background and Objective@#To design and fabricate a suction port adapter to use various sizes of suction cannulas with a wireless otoendoscope enabling ear cleaning under endoscopic guidance demonstrated using an ear examination simulator.@*Methods@#Design: Instrument Innovation. Setting: Tertiary Private Training Hospital. Patient: Ear Examination Simulator.@*Results@#The fabricated suction port adapters were able to hold the wireless otoendoscope and suction cannulas together, allowing simultaneous inspection of the ear canal and suctioning of ear canal debris using the Ear Examination Simulator.@*Conclusion@#Our prototype 3D-printed suction port adapters for a wireless otoendoscope may improve ear cleaning by enhancing the accuracy of suctioning debris and decreasing duration since they hold the suction cannulas in place under endoscopic guidance. They may aid ENT physicians in easier visualization and simultaneous ear cleaning of patients and improve ear cleaning techniques and times, especially among less experienced physicians, but actual clinical trials are needed to confirm this.

Development of 3D printed gastroretentive floating tablet devices for metronidazole

Background@#In this study, 3D printed floating tablet devices for Metronidazole (MTZ) were developed to prolong its exposure with Helicobacter pylori and eradicate it from causing peptic ulcer@*Objectives@#To utilize Quality by Design (QbD) in the development of the tablet devices through Fused Deposition Modelling (FDM) 3D printing. This aimed to develop and construct optimized design dimensions of tablet devices subject for characterization. @*Methodology@#Tablet designs were established using QbD, Design Failure Mode Effect and Analysis (DFMEA) and 2 factorial design. Four floating tablets devices were developed through FDM 3D printing using Polyvinyl alcohol (PVA) filament. Characterization tests determined their dimensions, density, floating mechanism, in vitro dissolution rate, drug release kinetics, surface morphology, infill and thermal characteristics. Significance of the QbD model was also assessed.@*Results@#Density of all devices were less than 1.004 g/cm . The floating Lag time (FLT) showed instant floatation and Total Floating Time (TFT) lasted for an average of 1 hour. Drug release kinetics show Korsmeyer-Peppas kinetics. Thermal characteristics fall within o o 186.12 C-187.27 C. 3D CTX-ray results show accuracy of printing 3D renders. Tablet device 3 exhibited the best surface morphology, longest floating time and slowest drug release.@*Conclusion@#The study successfully developed 3D printed floating tablet devices for Metronidazole with sustained release mechanism. Thus, utilizing QbD in pre-formulation studies using novel technology is essential in optimizing drug dosage forms. Plots from Design Expert Software show the significant design models.

Improved unilateral puncture PVP based on 3D printing technology for the treatment of osteoporotic vertebral compression fracture / 中国骨伤

OBJECTIVE@#To investigate the clinical effect of unilateral percutaneous vertebroplasty (PVP) combined with 3D printing technology for the treatment of thoracolumbar osteoporotic compression fracture.@*METHODS@#A total of 77 patients with thoracolumbar osteoporotic compression fractures from October 2020 to April 2022 were included in the study, all of which were vertebral body compression fractures caused by trauma. According to different treatment methods, they were divided into experimental group and control group. Thirty-two patients used 3D printing technology to improve unilateral transpedicle puncture vertebroplasty in the experimental group, there were 5 males and 27 females, aged from 63 to 91 years old with an average of (77.59±8.75) years old. Forty-five patients were treated with traditional bilateral pedicle puncture vertebroplasty, including 7 males and 38 females, aged from 60 to 88 years old with an average of(74.89±7.37) years old. Operation time, intraoperative C-arm X-ray times, anesthetic dosage, bone cement injection amount, bone cement diffusion good and good rate, complications, vertebral height, kyphotic angle (Cobb angle), visual analogue scale(VAS), Oswestry disability index (ODI) and other indicators were recorded before and after surgery, and statistically analyzed.@*RESULTS@#All patients were followed up for 6 to 23 months, with preoperative imaging studies, confirmed for thoracolumbar osteoporosis compression fractures, two groups of patients with postoperative complications, no special two groups of patients' age, gender, body mass index (BMI), time were injured, the injured vertebral distribution had no statistical difference(P>0.05), comparable data. Two groups of patients with bone cement injection, bone cement dispersion rate, preoperative and postoperative vertebral body height, protruding after spine angle(Cobb angle), VAS, ODI had no statistical difference(P>0.05). The operative time, intraoperative fluoroscopy times and anesthetic dosage were statistically different between the two groups(P<0.05). Compared with the traditional bilateral puncture group, the modified unilateral puncture group combined with 3D printing technology had shorter operation time, fewer intraoperative fluoroscopy times and less anesthetic dosage. The height of anterior vertebral edge, kyphosis angle (Cobb angle), VAS score and ODI of the affected vertebrae were statistically different between two groups at each time point after surgery(P<0.05).@*CONCLUSION@#In the treatment of thoracolumbar osteoporotic compression fractures, 3D printing technology is used to improve unilateral puncture PVP, which is convenient and simple, less trauma, short operation time, fewer fluoroscopy times, satisfactory distribution of bone cement, vertebral height recovery and kyphotic Angle correction, and good functional improvement.

Aplicação de tecnologias digitais em diversas áreas da cirurgia e traumatologia buco-maxilo-facial / Introduction of digital technologies in several areas of oral-maxillo-facial surgery

A integração do fluxo digital está se tornando cada vez mais comum na rotina da odontologia. A adoção de tecnologias como escaneamento dentário, reconstruções tridimensionais de estruturas anatômicas, medições precisas de tecidos duros e moles, simulações de procedimentos cirúrgicos com modelos virtuais de pacientes, prototipagem de modelos e criação de guias cirúrgicos são exemplos de ferramentas disponíveis para auxiliar tanto no diagnóstico quanto no planejamento e tratamento do paciente. Neste sentido, o objetivo deste trabalho foi descrever a aplicação do fluxo digital em seis tipos de procedimentos na área da cirurgia odontológica: cirurgia de implantes dentários, cirurgia de ancoragem de mini-implante ortodôntico, cirurgia de biópsia, cirurgia de avanço de maxila, cirurgia de ressecção de mandíbula e cirurgia de reconstrução mandibular com enxerto de crista ilíaca. A utilização do fluxo digital nas cirurgias proporcionou uma série de vantagens, tais como: um aumento na precisão dos procedimentos, a capacidade de realizar simulações cirúrgicas virtuais, uma comunicação aprimorada entre profissionais e pacientes, redução do tempo de cirurgia e maior previsibilidade dos resultados. No entanto, é importante ressaltar que o uso do fluxo digital requer investimentos em equipamentos mais caros e exige que os profissionais passem por uma curva de aprendizado para dominar essas novas tecnologias.

The integration of digital flow is becoming increasingly common in dentistry routine. The adoption of technologies such as dental scanning, three-dimensional reconstructions of anatomical structures, precise measurements of hard and soft tissues, simulations of surgical procedures with virtual patients models, prototyping models and creation of surgical guides are examples of tools available to assist in both diagnosis as well as patient planning and treatment. In this sense, the objective of this project was to describe the application of digital flow in six types of procedures in the area of dental surgery: dental implant surgery, orthodontic mini-implant anchorage surgery, biopsy surgery, maxillary advancement surgery, surgery of jaw resection and mandibular reconstruction with iliac crest bone graft. The use of digital flow in surgeries provided a series of advantages, such as: an increase in the precision of procedures, the ability to perform virtual surgical simulations, improved communication between professionals and patients, reduced surgery time and greater predictability of results. However, it is important to highlight that using digital flow requires investments in more expensive equipment and requires professionals to go through a learning curve to master these new technologies.

Methodology for Preoperative Planning of Bone Deformities Using Three-dimensional Modeling Software / Metodologia para planejamento pré-operatório de deformidades ósseas utilizando software de modelagem tridimensional

Abstract Rapid prototyping technology, known as three-dimensional (3D) printing, and its use in the medical field are advancing. Studies on severe bone deformity treatment with 3D printing showed benefits in postoperative outcomes thanks to this technology. Even so, preoperative planning guidance for surgeons is lacking. This technical note describes a practical step-by-step guide to help surgeons use this technology to optimize the therapeutic plan with free license software and an intuitive interface. This study aims to organize the 3D modeling process using a preoperative computed tomography (CT) scan. This technology allows a deeper understanding of the case and its particularities, such as the direction, planes, and dimensions of the deformity. Planning considering these topics may reduce the surgical time and result in better functional outcomes by understanding the deformity and how to correct it. Associating planning via software with 3D printing can further enhance this therapeutic method.

Resumo Observa-se o avanço da tecnologia de prototipagem rápida, conhecida como impressão tridimensional (3D) e seu uso na área médica. Existem estudos a respeito do tratamento de deformidades ósseas graves com impressão 3D, os quais mostram benefícios no resultado pós-operatório às custas do uso da tecnologia em questão. Ainda assim, nota-se a escassez quando o assunto é disponibilizar ao cirurgião orientações para planejamento pré-operatório. O objetivo desta nota técnica é descrever um passo-a-passo prático para auxiliar cirurgiões a utilizarem a tecnologia como ferramenta para otimizar o plano terapêutico, dispondo de um programa de licença gratuita e de interface intuitiva. Este é um estudo que visa a organização do processo de modelagem 3D, no qual foi utilizado um exame de tomografia computadorizada (TC) pré-operatória. Com esta tecnologia, é possível uma compreensão mais profunda do caso e suas particularidades como direção, planos e dimensões das deformidades. Acredita-se que um planejamento que leve em consideração tais tópicos gera redução do tempo cirúrgico e melhores resultados funcionais devido ao entendimento da deformidade e maneiras de correção. Associar o planejamento via software com a impressão 3D pode potencializar ainda mais na elaboração do método terapêutico.

Proposta de impressão em 3-D de ossos de pessoas idosas vitimadas de fratura: Considerações preliminares / Proposal for 3-D printing of bones from elderly people suffering from fractures: Preliminary considerations / Propuesta de impresión 3D de huesos de personas mayores con fracturas: Consideraciones preliminares

No ano de 1984, foi criada a primeira impressora do tipo 3-D pelo engenheiro de origem norte-americana, Dr. Charles Hull, sendo que, antes disso, mais especificamente a quatro (04) anos, o japonês Dr. Hideo Kodama, desenvolveu a técnica de estereolitografia, que consistia em uma prototipagem rápida, possuindo enquanto intuito, "criar" objetos usando para este intento, luz ultravioleta (UV), ou ainda, um projetor para endurecer uma resina do tipo líquida em plástico sólido e resistente, ficando posteriormente conhecida como a sigla SLA.1,2 Após dois (02) anos, em 1986, Hull patenteou a SLA e, com isso, ele teve a oportunidade de desenvolver a "3-D Systems Corp", presente até hoje, sendo está uma das maiores empresas do ramo e, desta forma, o primeiro objeto então escolhido pelo Dr. Hull para ser impresso, foi uma lâmpada feita com resina, um plástico sintético.

Impresión 3D aplicada a la planificación y la resolución quirúrgicas en la cirugía ortopédica. Serie de casos / 3D printing for surgical planning and resolution in orthopaedic surgery. Case series

Introducción: La popularidad de la cirugía asistida con impresión 3D ha crecido en los últimos 10 años. El poco empleo en nuestro medio no permite aprovechar para el paciente todas las aplicaciones y los beneficios de esta herramienta. Materiales y métodos: Estudio retrospectivo sobre enfermedad del miembro inferior en pacientes tratados en nuestra institución analizando cada etapa del proceso y su utilidad en la planificación, la ejecución quirúrgica y el desarrollo de implantes. Resultados: Se describen 12 casos en los que se utilizó la impresión 3D para tratar defectos acetabulares, resecciones tumorales óseas y secuelas en huesos largos. Conclusiones: Nuestra serie y la bibliografía revisada demuestran que la cirugía asistida con impresión 3D mejora la predictibilidad con lo planificado y reduce los tiempos quirúrgicos, el sangrado y la radiación intraoperatoria, a un costo accesible. Además, no se han comunicado complicaciones asociadas a esta tecnología. Nivel de Evidencia: IV

Introduction: The popularity of 3D printing-assisted surgery has surged over the previous decade. The tool's limited use in our context prevents us from taking advantage of all of its applications and benefits for the patient. materials and methods: A retrospective study on lower limb disease in patients treated at our institution, analyzing each stage of the procedure and its applicability in planning, surgical execution, and implant development. Results: We describe 12 cases in which 3D printing was used to treat acetabular defects, bone tumor resections, and long bone sequelae. Conclusions: Our series and the literature reviewed demonstrate that 3D printing-assisted surgery improves plan predictability while also reducing surgical times, bleeding, and intraoperative radiation at a reasonable cost. Furthermore, no complications from this technology have been reported. Level of Evidence: IV

Uso de modelos de impresión 3D en Ortopedia y Traumatología: Serie de casos / Use of 3D printing models in orthopedics and traumatology. Case series

Introducción: Comprender y tratar deformidades, defectos y fracturas complejas sigue siendo un desafío en el área de la Ortopedia y Traumatología. La aplicación de modelos de impresión 3D incluye el diagnóstico, la planificación quirúrgica, la creación de guías intraoperatorias e implantes y el entrenamiento quirúrgico. Las deformidades y fracturas articulares complejas representan un reto en el tratamiento quirúrgico debido a la complejidad tridimensional. La tecnología de impresión 3D permite simular la anatomía, la reducción de trazos fracturarios, osteotomías, y la dirección y longitud de los tornillos. El objetivo de este artículo es comunicar una serie de casos en los que se implementó la impresión 3D y presentar una revisión narrativa. Se describen dos casos de fractura de acetábulo, dos de escoliosis idiopática, una fractura del pilón tibial compleja y una fractura de astrágalo en los que se crearon modelos de impresión 3D para la planificación quirúrgica que resultaron beneficiosos tanto para el paciente como para el equipo quirúrgico. Conclusiones: Con el auge de la impresión 3D en el área de la Ortopedia y Traumatología, podremos facilitar el entendimiento de fracturas y deformidades complejas y mejorar las planificaciones prequirúrgicas. El tiempo de producción del modelo puede demorarse y ser una limitación para su uso en urgencias. Aún faltan estudios para evaluar los beneficios significativos para el paciente y el equipo médico, como la reducción del tiempo operatorio, la pérdida de sangre intraoperatoria y la exposición a la radiación. Nivel de Evidencia: IV

Introduction: Understanding and treating deformities, defects and complex fractures remains a challenge in the area of orthopedics and traumatology. 3D printing models are used for diagnostics, surgical planning, the manufacturing of intraoperative guides and implants, and surgical training. The objective of our work was to report on a series of cases where 3D printing was implemented in our service and to carry out a narrative review. The case series includes two acetabular fractures, two idiopathic scoliosis, a complex tibial pilon fracture, and a talar fracture. 3D printing models were used for surgery planning, which benefited both the patient and the surgical team. Conclusions: With the rise of 3D printing in orthopedics and traumatology, we are able to better understand fractures and complex deformities, as well as improve preoperative planning. The model's production timelines may be delayed, limiting its usefulness in an emergency. There are yet insufficient studies that report substantial benefits to the patient and medical team, such as reduced surgical time, intraoperative blood loss, and radiation exposure. Level of Evidence: IV

Microtensile bond strength of resin cements to 3-D printed and milled temporary restorative resins / Resistencia de unión en microtracción de cementos resinosos a resinas para provisionales impresas y fresadas

Abstract To evaluate the microtensile bond strength (µTBS) of two resin cements to 3D printed and milled CAD/CAM resins used for provisional fixed partial dentures. Blocks (5 x 5 x 5 mm) of three 3D-printed resins (Cosmos3DTemp / Yller; Resilab3D Temp / Wilcos and SmartPrint BioTemp, / MMTech) were printed (Photon, Anycubic Technology Co.). A milled material (VitaCAD-Temp, VITA) was used as control. Half the specimens were sandblasted and the rest were untreated. Two blocks were bonded with the corresponding resin cement: PanaviaV5 (Kuraray Noritake) and RelyX Ultimate (3M Oral Care). After 24 hours, the bonded blocks were sectioned into 1 x 1 mm side sticks. Half the beams were tested for µTBS and the other half was thermocycled (5000 cycles, 30s dwell-time, 5s transfer time) before µTBS testing. A four way Generalized Linear Model (material*sandblasting*cement*aging) analysis was applied. VITA exhibited the lowest µTBS, regardless of the cement, sandblasting and thermocycling. Sandblasting significantly improved the µTBS of VIT, especially after aging, but did not improve the µTBS of 3D printed resins. Sandblasting was not beneficial for 3D printed resins, although is crucial for adhesive cementation of milled temporary resins. Airborne particle abrasion affects the integrity of 3D-printed resins, without producing a benefit on the microtensile bond strength of these materials. However, sandblasting is crucial to achieve a high bond strength on milled temporary resins.

Resumen Evaluar la resistencia adhesiva en microtracción (µTBS) de dos cementos resinosos a resinas CAD/CAM impresas y fresadas indicadas para restauraciones provisionales. Bloques (5 x 5 x 5mm) de tres resinas impresas (Cosmos3DTemp / Yller; Resilab3D Temp / Wilcos and SmartPrint BioTemp, / MMTech) y una resina fresada (VitaCAD-Temp, VITA) fueron fabricados. La mitad de los especímenes fueron arenados y el resto no recibió tratamiento mecánico. Dos bloques con condiciones de tratamiento iguales fueron cementados con cemento resinoso (PanaviaV5 / Kuraray Noritake y RelyX Ultimate / 3M Oral Care). Después de 24 horas los bloques fueron seccionados en palitos de 1 mm² de área. En la mitad de los especímenes se midió la TBS inmediatamente y el resto fue termociclado (5000 ciclos, 30s remojo, 5s transferencia) antes de la prueba de TBS. Se aplica un análisis estadístico por Modelo Linear General con 4 factores (material*arenado*cemento*termociclado). La resina VITA presentó la menor µTBS, independientemente del cemento usado, el arenado y el termociclado. Sin embargo, el arenado aumentó la µTBS de VIT, especialmente después del termociclado. Por otro lado, el arenado no resultó en un aumento significativo de la µTBS de las resinas impresas. El arenado no fue beneficiosos para las resinas impresas, aunque es un paso crucial para la cementación adhesive de las resinas fresadas. El arenado afecta la integridad de las capas de las resinas impresas, sin generar un beneficio en la TBS.

3D Foot Anthropometric Measurements Under Two Weight- Bearing Conditions for Ergonomic Design of Foot-Related Products / Mediciones Antropométricas del Pie en 3D Bajo Dos Condiciones de Soporte de Peso para el Diseño Ergonómico de Productos Relacionados con los Pies

SUMMARY: This study collected 3D models of the left and right feet from 317 Chinese youth (155 females and 162 males) under half weight-bearing and no weight-bearing conditions. Thirteen dimensions and one angle were taken for each sample. By measuring 13 foot dimensions and 1 angle, this study comprehensively investigated the differences in foot shape between genders and the bilateral differences, as well as the foot shape differences under different conditions. The results showed that regardless of the condition, male foot dimensions were significantly larger than those of females. However, female foot shape was not simply a scaled-down version of male foot shape. On the contrary, the average angle of female feet was greater than that of males under both conditions, indicating a higher prevalence of hallux valgus in females. Both males and females exhibited significant correlation in foot dimensions between the left and right feet, with minimal differences. Under the half weight-bearing condition, the average foot length, width, and circumference were significantly larger than the corresponding measurements under the no weight-bearing condition, while the average height and angle were significantly smaller. Therefore, when designing footwear and foot-related medical rehabilitation aids, it is important to consider foot shape and dimensions under different conditions as a reference. The results of this study provide manufacturers of foot- related products with more detailed data support and are of significant value to the field of medical foot morphology research.

Este estudio recolectó modelos 3D de los pies izquierdo y derecho de 317 jóvenes chinos (155 mujeres y 162 hombres) en condiciones de carga media de peso y sin carga de peso. Para cada muestra se tomaron trece dimensiones y un ángulo. Al medir 13 dimensiones del pie y 1 ángulo, se investigó exhaustivamente las diferencias en la forma del pie entre ambos sexos y sus diferencias bilaterales, así como las diferencias en la forma del pie en diferentes condiciones. Los resultados mostraron que, independientemente de la condición, las dimensiones del pie de los hombres, estos eran significativamente más grandes que los de las mujeres. Sin embargo, la forma del pie femenino no era simplemente una versión reducida de la forma del pie masculino. Por el contrario, el ángulo promedio de los pies de las mujeres fue mayor que el de los hombres en ambas condiciones, lo que indica una mayor prevalencia de hallux valgus en las mujeres. Tanto hombres como mujeres exhibieron una correlación significativa en las dimensiones del pie, entre el pie izquierdo y el derecho, con diferencias mínimas. Bajo la condición de medio soporte de peso, la longitud, el ancho y la circunferencia promedio del pie fueron significativamente mayores que las medidas correspondientes bajo la condición sin soporte de peso, mientras que la altura y el ángulo promedio fueron significativamente más pequeños. Por lo tanto, al diseñar calzado y dispositivos médicos de rehabilitación relacionados con los pies, es importante tener en consideración la forma y las dimensiones del pie en diferentes condiciones como referencia. Los resultados de este estudio, brindan a los fabricantes de productos relacionados con los pies un soporte de datos más detallado y son de gran valor para el campo de la investigación médica de la morfología del pie.

Analysis of the Mechanical Behavior of Porcine Graft Fixation in a Polyurethane Block Using a 3D-printed PLA Interference Screw / Análise do comportamento mecânico da fixação do enxerto suíno em um bloco de poliuretano usando um parafuso de interferência PLA impresso em 3D

Abstract Objective The interest in using 3D printing in the healthcare field has grown over the years, given its advantages and potential in the rapid manufacturing of personalized devices and implants with complex geometries. Thus, the aim of the present study was to compare the mechanical fixation behavior of a 3D-printed interference screw, produced by fused deposition modeling of polylactic acid (PLA) filament, with that of a titanium interference screw. Methods Eight deep flexor porcine tendons, approximately 8 mm wide and 9 cm long, were used as graft and fixed to a 40 pounds-per-cubic-foot (PCF) polyurethane block at each of its extremities. One group was fixed only with titanium interference screws (group 1) and the other only with 3D-printed PLA screws (BR 20 2021 018283-6 U2) (group 2). The tests were conducted using an EMIC DL 10000 electromechanical universal testing machine in axial traction mode. Results Group 1 (titanium) obtained peak force of 200 ± 7 N, with mean graft deformation of 8 ± 2 mm, and group 2 (PLA) obtained peak force of 300 ± 30 N, and mean graft deformation of 7 ± 3 mm. Both the titanium and PLA screws provided good graft fixation in the polyurethane block, with no slippage or apparent deformation. In all the samples, the test culminated in graft rupture, with around 20 mm of deformation in relation to the initial length. Conclusion The 3D-printed PLA screw provided good fixation, similar to that of its titanium counterpart, producing satisfactory and promising results.

Resumo Objetivo O interesse em utilizar a impressão 3D na área da saúde tem crescido ao longo dos anos, dadas as suas vantagens e o seu potencial na rápida fabricação de dispositivos e implantes personalizados com geometrias complexas. Assim, o objetivo do presente estudo foi comparar o comportamento de fixação mecânica de um parafuso de interferência impresso em 3D, produzido pela modelagem fundida de deposição do filamento de ácido polilático (PLA), com o de um parafuso de interferência de titânio. Métodos Oito tendões suínos flexores profundos, de aproximadamente 8 mm de largura e 9 cm de comprimento, foram utilizados como enxerto e fixados em um bloco de poliuretano de 40 PCF em cada uma de suas extremidades. Um grupo foi fixado apenas com parafusos de interferência de titânio (grupo 1) e o outro apenas com parafusos PLA impressos em 3D (BR 20 2021 018283-6 U2) (grupo 2). Os testes foram realizados utilizando uma máquina de teste universal eletromecânica EMIC DL 10.000 no modo de tração axial. Resultados O grupo 1 (titânio) obteve força máxima de 200 ± 7 N com deformação média do enxerto de 8 ± 2 mm, e a força máxima do grupo 2 (PLA) foi de 300 ± 30 N e deformação média do enxerto de 7 ± 3 mm. Ambos os parafusos de titânio e PLA forneceram boa fixação de enxerto no bloco de poliuretano, sem deslizamento ou deformação aparente. Em todas as amostras o teste culminou na ruptura do enxerto, com cerca de 20 mm de deformação em relação ao comprimento inicial. Conclusão O parafuso PLA impresso em 3D proporcionou boa fixação, semelhante à de sua contraparte de titânio, produzindo resultados satisfatórios e promissores.

Nuevos Recursos Digitales y 3D en la Enseñanza de Anatomía. Experiencia Internacional Reportada en el "Sectra Users Meeting 2019", Karolinska Institutet, Suecia, antes de la Pandemia de COVID-19 / New Digital and 3D Resources in the Teaching of Anatomy. International Experience Reported in the "Sectra Users Meeting 2019", Karolinska Institutet, Sweden, Before the Pandemic COVID-19

El uso de nuevos recursos tecnológicos en la enseñanza de anatomía ha impulsado la necesidad de adaptar el modelo educativo haciéndolo más centrado en el estudiante, dinámico y participativo mediante herramientas digitales y 3D; orientando los conocimientos hacia su aplicación clínica, pero bajo un ajuste curricular que tiende a cursar menos horas presenciales en aula o laboratorio. Este trabajo describe la experiencia local de una nueva Escuela de Medicina en Chile, reportada el año 2018, además y otros trabajos de centros formadores presentados en el "SECTRA Users Meeting 2019 Estocolmo", Karolinska Institutet, Suecia. Este trabajo describe los reportes orales sobre la aplicación de nuevos recursos digitales como; la mesa de disección digital táctil SECTRA® y modelos anatómicos cadavéricos impresos en 3D Erler-Zimmer®, bases de datos sobre anatomía digital, además, su impacto en el desempeño académico, reportado por usuarios de diferentes países, tales como: Australia, Canadá, Chile, China, Colombia, Estados Unidos de Norteamérica (EUA) y Suecia. Los datos fueron recopilados y analizados a partir de la información reportada en las presentaciones orales y resúmenes entregados por los expositores. La gran mayoría de los países expositores declararon el uso combinado de recursos digitales y 3D sumados a los tradicionales para la enseñanza de anatomía. Sólo el representante de EUA declaró usar exclusivamente recursos digitales (en laboratorio y en línea), experiencia correspondiente a una joven e innovadora escuela de medicina. La mayoría de los centros docentes declaró utilizar la mesa de disección digital en una amplia proporción de sus contenidos curriculares, en asociación a plataformas tipo RIS/PACS como IDS7 portal de SECTRA o las utilizadas por el centro formador. El uso de nuevas tecnologías digitales y 3D ha ganado un importante espacio en el currículum de la enseñanza de anatomía, complementando el uso de los recursos tradicionales.

SUMMARY: The use of new technological resources in the teaching of anatomy has promoted the need to adapt the educational model, making it more student-centered, dynamic, and participatory through digital and 3D tools, directing the knowledge towards its clinical application, but under a curricular adjustment that tends to take fewer contact hours in the classroom or laboratory. This work describes the local experience of a new School of Medicine in Chile, reported in 2018, and other work from training centers presented at the "SECTRA Users Meeting 2019 Stockholm", Karolinska Institutet, Sweden. This work describes the oral reports on the application of new digital resources such as; the SECTRA® digital tactile dissection table and Erler- Zimmer® 3D printed cadaveric anatomical models, databases on digital anatomy, in addition, its impact on academic performance, reported by users from different countries, such as Australia, Canada, Chile, China, Colombia, United States of America (USA) and Sweden. The data was collected and analyzed from the information reported in the oral presentations and summaries delivered by the speakers.The vast majority of the exhibiting countries declared the combined use of digital and 3D resources added to the traditional ones for teaching anatomy. Only the representative from the USA stated that they exclusively used digital resources (in the laboratory and online), an experience corresponding to a young and innovative medical school. Most of the educational centers stated that they used the digital dissection table in a large proportion of their curricular contents, in association with RIS/PACS-type platforms such as the IDS7 SECTRA portal or those used by the training center. The use of new digital and 3D technologies has gained an important space in the anatomy teaching curriculum, complementing the use of traditional resources.

Sex estimation based on foramen magnum: a three-dimensional geometric morphometrics approach / Estimación del sexo basado en el foramen magno: un enfoque de morfometría geométrica tridimensional

SUMMARY: The foramen magnum is an important topographic opening which connects cranial cavity and spinal canal. The analysis of the bone material established that there are differences in the shape of the foramen magnum between individuals. The aim of this study was to determine sex based on shape and size of foramen magnum using geometric morphometrics method. A study was performed on three-dimensional models (3D models) of 214 human skulls of known sex and known age (141 male skulls and 73 female skulls). The skulls are located at the museum of Medical Faculty, University of Sarajevo. Skulls belong to Bosnian population from the mid-twentieth century. All examined skulls were scanned with a laser scanner to obtain their 3D models. On 3D models of the examined skulls, four landmarks were marked on foramen magnum. Analysis of sex determination was performed using the MorphoJ program. Results of this study showed that there are sex differences in the shape and size of the foramen magnum. Sex determination based on the shape and size of the foramen magnum was showed 65.25 % accuracy for male and 63.01 % accuracy for female using geometric morphometrics method. Examination of the effect of size of foramen magnum on sexual dimorphism of shape of foramen magnum showed a statistically significant effect. Sex determination based just on the shape of foramen magnum using geometric morphometrics method was possible with 62.41 % accuracy for male and 58.90 % accuracy for female on examined sample. Sex differences on shape and size of foramen magnum were found using geometric morphometrics method on three-dimensional models of the examined skulls. The percentage of accuracy was higher for male based on the shape and size of the foramen magnum than for female.

El foramen magno es una importante abertura topográfica que conecta la cavidad craneal y el canal espinal. El análisis del material óseo estableció que existen diferencias en la forma del foramen magno entre individuos. El objetivo de este estudio fue determinar el sexo en función de la forma y el tamaño del foramen magno utilizando morfometría geométrica. El estudio se realizó en modelos tridimensionales (modelos 3D) de 214 cráneos humanos de sexo y edad conocidos (141 cráneos masculinos y 73 cráneos femeninos). Los cráneos se encuentran en el museo de la Facultad de Medicina de la Universidad de Sarajevo. Los cráneos pertenecen a población bosnia de mediados del siglo XX. Todos los cráneos examinados fueron escaneados con un escáner láser para obtener sus modelos 3D. En los modelos 3D de los cráneos examinados, se marcaron cuatro puntos de referencia en el foramen magno. El análisis de determinación de sexo se realizó utilizando el programa MorphoJ. Los resultados de este estudio mostraron que existen diferencias de sexo en la forma y el tamaño del foramen magno. La determinación del sexo basada en la forma y el tamaño del foramen magno mostró una precisión del 65,25 % para los hombres y del 63,01 % para las mujeres utilizando morfometría geométrica. El examen del efecto del tamaño del foramen magno sobre el dimorfismo sexual de la forma del foramen magno mostró un efecto estadísticamente significativo. La determinación del sexo basada solo en la forma del foramen magno utilizando morfometría geométrica fue posible con una precisión del 62,41 % para los hombres y del 58,90 % para las mujeres en la muestra examinada. Se encontraron diferencias de sexo en la forma y el tamaño del foramen magno utilizando morfometría geométrica en modelos tridimensionales de los cráneos examinados. El porcentaje de precisión fue mayor para los hombres en función de la forma y el tamaño del foramen magno que para las mujeres.

Evaluation of angles of the tracheobronchial tree with the 3-dimensional reconstruction method: a morphometric and radiologic study / Evaluación de los ángulos del árbol traqueobronquial con el método de reconstrucción tridimensional: un estudio morfométrico y radiológico

SUMMARY: The objective of the current research is to assess the branching angles of the tracheobronchial tree and the correlation between these angles and the lung volume using the 3-dimensional reconstruction method. Thorax CT (computed tomography) images of 150 individuals, who were over 18 years of age and did not have any pathology on CT, were obtained retrospectively. A 3-dimensional reconstruction of the trachea, bronchi, and lungs was carried out. External and internal angles between the trachea and main bronchi, between the main bronchi and lobar bronchi, and between the lobar bronchi were measured. The volume measurement of the right and left lungs was performed. The individuals included in the study were grouped by sex and age (20-40 years, 41-61 years, and 62-87 years). The left subcarinal angle (LSA), total subcarinal angle (TSA), and left interbronchial angle (LIA) were found to be greater in the 62-87 age group. Both the external angle (LULB-LMBE) and the internal angle (LULB- LMBI) between the left upper lobar bronchus and the left main bronchus were observed to be greater in males. In males, a statistically significant negative moderate correlation was identified between the right lung volume and the right subcarinal angle (RSA). In females, a statistically significant positive moderate correlation was revealed between the external (RULB-IBE) and internal angles (RULB-IBI) between the right upper lobar bronchus and the intermediate bronchus, and the right lung volume. In the literature review we performed, we did not find any studies investigating the correlation between the branching angles of the tracheobronchial tree and the lung volume using the 3-dimensional reconstruction method. Therefore, we are of the opinion that our study will contribute to the literature.

El objetivo de la investigación fue evaluar los ángulos de ramificación del árbol traqueobronquial y la correlación entre estos ángulos y el volumen pulmonar utilizando el método de reconstrucción tridimensional. Se obtuvieron retrospectivamente imágenes de tomografía computarizada de tórax de 150 individuos mayores de 18 años sin patología. Se realizó una reconstrucción tridimensional de la tráquea, los bronquios y los pulmones. Se midieron los ángulos externo e interno entre la tráquea y los bronquios principales, entre los bronquios principales y los bronquios lobares, y entre los bronquios lobares. Se realizó la medición del volumen de los pulmones derecho e izquierdo. Los individuos incluidos en el estudio fueron agrupados por sexo y edad (20-40 años, 41-61 años y 62-87 años). Se encontró que el ángulo subcarinal izquierdo, el ángulo subcarinal total y el ángulo interbronquial izquierdo eran mayores en el grupo de edad de 62 a 87 años. Tanto el ángulo externo (LULB-LMBE) como el ángulo interno (LULB-LMBI) entre el bronquio lobular superior izquierdo y el bronquio principal izquierdo era mayor en los hombres. En los hombres, se identificó una correlación moderada negativa estadísticamente significativa entre el volumen pulmonar derecho y el ángulo subcarinal derecho. En mujeres, se reveló una correlación positiva moderada estadísticamente significativa entre los ángulos externos (RULB-IBE) e internos (RULB-IBI) entre el bronquio lobar superior derecho y el bronquio intermedio, y el volumen pulmonar derecho. En la revisión bibliográfica que realizamos, no encontramos ningún estudio que analizara la correlación entre los ángulos de ramificación del árbol traqueobronquial y el volumen pulmonar utilizando el método de reconstrucción tridimensional. Por lo tanto, consideramos que nuestro estudio contribuirá a la literatura especializada del tema.

Morphometric examination of the trachea and bronchi in follow-up computed tomography scans of COVID-19 patients / Examen morfométrico de la tráquea y los bronquios en tomografías computarizadas de seguimiento de pacientes con COVID-19

SUMMARY: The purpose of this study is to evaluate changes in the trachea and bronchi using 3-dimensional reconstruction images obtained from the initial and follow-up computed tomography (CT) scans of COVID-19 patients. A hundred COVID-19 patients over the age of 18 were included in our study. CT images were transferred to Mimics software, and a 3-dimensional reconstruction of the trachea and bronchi was performed. The initial and follow-up CT images of COVID-19 patients were graded as none (grade 0), mild (grade 1), moderate (grade 2), and severe (grade 3) according to the total lung severity score. The patients were divided into progression and regression groups according to the grade increase/decrease between the initial and follow-up CTs. Moreover, the patients were divided into groups as 0-2 weeks, 2-4 weeks, 4-12 weeks, and over 12 weeks according to the duration between the initial and follow-up CTs. The mean cross-sectional area, circumference, and diameter measurements of the right upper lobar bronchus, intermediate bronchus, middle lobar bronchus, and left lower lobar bronchus decreased in the follow-up CTs of the progression group. This decrease was not found to be statistically significant. In the follow-up CTs of the regression group, the left upper lobar bronchus and left lower lobar bronchus measurements increased but not statistically significant. Upon comparing the onset of the disease and the follow-up period, statistically significant changes did not occur in the trachea, main bronchus, and lobar bronchus of COVID-19 patients.

El propósito de este estudio fue evaluar los cambios en la tráquea y los bronquios utilizando imágenes de reconstrucción tridimensionales obtenidas de las tomografías computarizadas (TC) iniciales y de seguimiento de pacientes con COVID-19. En nuestro estudio se incluyeron 100 pacientes con COVID-19 mayores de 18 años. Las imágenes de TC se transfirieron al software Mimics y se realizó una reconstrucción tridimensional de la tráquea y los bronquios. Las imágenes de TC iniciales y de seguimiento de los pacientes con COVID-19 se calificaron como ninguna (grado 0), leve (grado 1), moderada (grado 2) y grave (grado 3) según la puntuación total de gravedad pulmonar. Los pacientes se dividieron en grupos de progresión y regresión según el aumento/disminución del grado entre las TC iniciales y de seguimiento. Además, los pacientes se dividieron en grupos de 0 a 2 semanas, de 2 a 4 semanas, de 4 a 12 semanas y de más de 12 semanas según la duración entre la TC inicial y la de seguimiento. Las mediciones medias del área transversal, la circunferencia y el diámetro del bronquio lobar superior derecho, el bronquio intermedio, el bronquio lobar medio y el bronquio lobar inferior izquierdo disminuyeron en las TC de seguimiento del grupo de progresión. No se encontró que esta disminución fuera estadísticamente significativa. En las TC de seguimiento del grupo de regresión, las mediciones del bronquio lobar superior izquierdo y del bronquio lobar inferior izquierdo aumentaron pero no fueron estadísticamente significativas. Al comparar el inicio de la enfermedad y el período de seguimiento, no ocurrieron cambios estadísticamente significativos en la tráquea, el bronquio principal y el bronquio lobar de los pacientes con COVID-19.

Application of 3D Printing Technology in the Treatment of Hoffa's Fracture Nonunion / Aplicação da tecnologia de impressão 3D no tratamento da pseudartrose da fratura de Hoffa

Abstract Objective To evaluate a proposed three-dimensional (3D) printing process of a biomodel developed with the aid of fused deposition modeling (FDM) technology based on computed tomography (CT) scans of an individual with nonunion of a coronal femoral condyle fracture (Hoffa's fracture). Materials and Methods Thus, we used CT scans, which enable the evaluation of the 3D volumetric reconstruction of the anatomical model, as well as of the architecture and bone geometry of sites with complex anatomy, such as the joints. In addition, it enables the development of the virtual surgical planning (VSP) in a computer-aided design (CAD) software. This technology makes it possible to print full-scale anatomical models that can be used in surgical simulations for training and in the choice of the best placement of the implant according to the VSP. In the radiographic evaluation of the osteosynthesis of the Hoffa's fracture nonunion, we assessed the position of the implant in the 3D-printed anatomical model and in the patient's knee. Results The 3D-printed anatomical model showed geometric and morphological characteristics similar to those of the actual bone. The position of the implants in relation to the nonunion line and anatomical landmarks showed great accuracy in the comparison of the patient's knee with the 3D-printed anatomical model. Conclusion The use of the virtual anatomical model and the 3D-printed anatomical model with the additive manufacturing (AM) technology proved to be effective and useful in planning and performing the surgical treatment of Hoffa's fracture nonunion. Thus, it showed great accuracy in the reproducibility of the virtual surgical planning and the 3D-printed anatomical model.

Resumo Objetivo Avaliar uma proposta de processo de impressão tridimensional (3D) de um biomodelo preparado com o auxílio da tecnologia de modelagem por deposição de material fundido (fused deposition modeling, FDM, em inglês) a partir de imagens de tomografia computadorizada (TC) de um indivíduo com pseudartrose de fratura coronal do côndilo femoral (fratura de Hoffa). Materiais e Métodos Para tanto, utilizamos imagens de TC, que permitem estudar a reconstrução volumétrica 3D do modelo anatômico, além da arquitetura e geometria óssea de sítios de anatomia complexa, como as articulações. Também permite o planejamento cirúrgico virtual (PCV) em um programa de desenho assistido por computador (computer-aided design, CAD, em inglês). Essa tecnologia possibilita a impressão de modelos anatômicos em escala real que podem ser utilizados em simulações cirúrgicas para o treinamento e a escolha do melhor posicionamento do implante de acordo com o PCV. Na avaliação radiográfica da osteossíntese da pseudartrose de Hoffa, verificou-se a posição do implante no modelo anatômico impresso em 3D e no joelho do paciente. Resultados O modelo anatômico impresso em 3D apresentou características geométricas e morfológicas semelhantes às do osso real. O posicionamento dos implantes em relação à linha de pseudartrose e pontos anatômicos foram bastante precisos na comparação do joelho do paciente com o modelo anatômico impresso em 3D. Conclusão A utilização do modelo anatômico virtual e do modelo anatômico impresso em 3D com a tecnologia de manufatura aditiva (MA) foi eficaz e auxiliou o planejamento e a realização do tratamento cirúrgico da pseudartrose da fratura de Hoffa. Desta forma, foi bastante preciso na reprodutibilidade do planejamento cirúrgico tanto virtual quanto no modelo anatômico impresso em 3D.

Biomateriales y tecnologías de impresión 3D en entrenamiento quirúrgico en otorrinolaringología: una revisión / Biomaterials and technologies of 3D printing in surgical training on otorhinolaryngology: a revision

La tecnología de fabricación aditiva o impresión 3D se ha posicionado como una herramienta transversal y de uso creciente en el mundo productivo y científico que ha otorgado la posibilidad de diseñar y crear elementos y modelos de diversa complejidad. En el área biomédica ha presentado un aumento significativo de sus aplicaciones a través del tiempo, actualmente teniendo relevancia en ámbitos como el planeamiento quirúrgico, la creación de prótesis, modelos anatómicos para educación y entrenamiento quirúrgico. Actualmente existen diversas dificultades que limitan la formación quirúrgica, especialmente en ciertas áreas de la otorrinolaringología como la cirugía de oído. El objetivo de la presente revisión narrativa fue actualizar los usos de la tecnología de impresión 3D para la creación de modelos para entrenamiento quirúrgico en otorrinolaringología, destacando sus potenciales usos en otología, rinología, cirugía de base de cráneo y vía aérea.

Additive manufacturing technology or 3D printing has positioned itself as a cross-cutting tool of increasing use in the productive and scientific world that has given the possibility of designing and creating different elements and models of varying complexity. In the biomedical area, it has presented a significant increase in its applications over time, currently having relevance in areas such as surgical planning, the creation of prostheses, anatomical models for education and surgical training. Currently there are various difficulties that limit surgical training, especially in certain areas of otorhinolaryngology such as ear surgery. The objective of this narrative review was to update the uses of 3D printing technology for the creation of models for surgical training in otorhinolaryngology, highlighting its potential uses in otology, rhinology, skull base and airway surgery.

Prototyping and 3D printing of computed tomography images with an emphasis on soft tissues, especially muscles, for teaching human anatomy / Prototipado e impresión 3D de imágenes de tomografía computarizada con énfasis en los tejidos blandos, especialmente músculos, para la enseñanza de la anatomía humana

SUMMARY: The study on cadavers, although considered fundamental in the teaching of human anatomy, is limited in several universities, mainly due to the acquisition and manipulation of cadaveric material. Throughout history, several artificial anatomical models have been used to complement the real anatomical pieces. The present study offers a new alternative: the making of three-dimensional models from Computed Tomography (3D-CT) patient image acquisition. CT images from the USP University Hospital database were used. Patients underwent examinations for reasons other than the present study and were anonymized to maintain confidentiality. The CT slices obtained in thin cross-sections (approximately 1.0 mm thick) were converted into three-dimensional images by a technique named Volume Rendering for visualization of soft tissue and bone. The reconstructions were then converted to an STL (Standard Triangle Language) model and printed through two printers (LONGER LK4 Pro® and Sethi S3®), using PLA and ABS filaments. The 3D impressions of the thigh and leg muscles obtained better visual quality, being able to readily identify the local musculature. The images of the face, heart, and head bones, although easily identifiable, although seemed to present lower quality aesthetic results. This pilot study may be one of the first to perform 3D impressions of images from CT to visualize the musculature in Brazil and may become an additional tool for teaching.

El estudio en cadáveres, a pesar de considerarse un aspecto fundamental en la enseñanza de la anatomía humana, se encuentra limitado en varias universidades, principalmente por la adquisición y manipulación de material cadavérico. A lo largo de la historia se han utilizado varios modelos anatómicos artificiales para complementar las piezas anatómicas reales. El presente estudio ofrece una nueva alternativa: la elaboración de modelos tridimensionales a partir de la adquisición de imágenes de pacientes por Tomografía Computarizada (3D-CT). Se utilizaron imágenes de TC de la base de datos del Hospital Universitario de la USP. Los pacientes se sometieron a exámenes por razones distintas al presente estudio y fueron anonimizados para mantener la confidencialidad. Los cortes de TC obtenidos en secciones transversales delgadas (aproximadamente 1,0 mm de grosor) se convirtieron en imágenes tridimensionales mediante una técnica denominada Volume Rendering para la visualización de tejido blando y hueso. Luego, las reconstrucciones se convirtieron a un modelo STL (Standard Triangle Language) y se imprimieron a través de dos impresoras (LONGER LK4 Pro® y Sethi S3®), utilizando filamentos PLA y ABS. Se obtuvo una mejor calidad visual de las impresiones 3D de los músculos del muslo y la pierna, pudiendo identificar fácilmente la musculatura local. Las imágenes de la cara, el corazón y los huesos de la cabeza, aunque fácilmente identificables, parecían presentar resultados estéticos de menor calidad. Este estudio piloto puede ser uno de los primeros en realizar impresiones 3D de imágenes de TC para visualizar la musculatura y podría ser en una herramienta adicional para la enseñanza.