Developing the OpenFlexure Microscope towards medical use: technical and social challenges of developing globally accessible hardware for healthcare.

The OpenFlexure Microscope is an accessible, three-dimensional-printed robotic microscope, with sufficient image quality to resolve diagnostic features including parasites and cancerous cells. As access to lab-grade microscopes is a major challenge in global healthcare, the OpenFlexure Microscope has been developed to be manufactured, maintained and used in remote environments, supporting point-of-care diagnosis. The steps taken in transforming the hardware and software from an academic prototype towards an accepted medical device include addressing technical and social challenges, and are key for any innovation targeting improved effectiveness in low-resource healthcare. This article is part of the Theo Murphy meeting issue 'Open, reproducible hardware for microscopy'.

Novel 3D printed universal conical holder for eye plaque quality assurance.

PURPOSE: For the custom-built construction of eye plaques, the iodine (I-125) seeds of different source strengths are recycled in our eye plaque program. To return I-125 seeds to the correct lot, we developed a novel 3D-printed conical plaque QA holder for relative assay for eye plaques. MATERIALS AND METHODS: A universal 3D-printed conical plaque holder was designed to accommodate six plaque sizes and fit reproducibly in a well-type dose calibrator. A reproducibility test was used to compare the plaque placement consistency in the holder versus without the holder. Plaque assays were performed for assembled plaques both before implant and after explant. The explant reading was compared with the implant reading adjusted for decay, and the relative error was calculated. The plaque response fraction (PRF) is defined as the fraction of well chamber implant reading over the total seed strength for a plaque. The PRF was aggregated for each individual plaque to confirm the seed lot before implant. RESULTS: The reproducibility test showed the chamber reading's relative standard deviation of 0.40% with the QA holder compared to 0.68% without it. The batch relative assay was performed for 251 plaques. The absolute value of measurement deviation between explant and decay-corrected implant readings is 0.89% ± 0.86% (mean ± standard deviation). The PRFs for individual plaques range from 36.49% to 49.87%, with a maximum standard deviation of 2%. CONCLUSIONS: This novel 3D-printed QA holder provides reproducible setup for assaying assembled eye plaques in a well chamber. Batch relative assay can validate the seed batch used and plaque integrity during the implant without assaying individual seeds, saving valuable physicist time and radiation exposure from seed handling.

TruD technology for the study of epi- and endothelial tubes in vitro.

Beyond the smallest organisms, animals rely on tubes to transport cells, oxygen, nutrients, waste products, and a great variety of secretions. The cardiovascular system, lungs, gastrointestinal and genitourinary tracts, as well as major exocrine glands, are all composed of tubes. Paradoxically, despite their ubiquitous importance, most existing devices designed to study tubes are relatively complex to manufacture and/or utilize. The present work describes a simple method for generating tubes in vitro using nothing more than a low-cost 3D printer along with general lab supplies. The technology is termed "TruD", an acronym for true dimensional. Using this technology, it is readily feasible to cast tubes embedded in ECM with easy access to the lumen. The design is modular to permit more complex tube arrangements and to sustain flow. Importantly, by virtue of its simplicity, TruD technology enables typical molecular cell biology experiments where multiple conditions are assayed in replicate.

Enhanced Interstitial Fluid Extraction and Rapid Analysis via Vacuum Tube-Integrated Microneedle Array Device.

Advancing the development of point-of-care testing (POCT) sensors that utilize interstitial fluid (ISF) presents considerable obstacles in terms of rapid sampling and analysis. Herein, an innovative strategy is introduced that involves the use of a 3D-printed, hollow microneedle array patch (MAP), in tandem with a vacuum tube (VT) connected through a hose, to improve ISF extraction efficiency and facilitate expedited analysis. The employment of negative pressure by the VT allows the MAP device to effectively gather ≈18 µL of ISF from the dermis of a live rabbit ear within a concise period of 5 min. This methodology enables the immediate and minimally invasive measurement of glucose levels within the body, employing personal healthcare meters for quantification. The fusion of the VT and MAP technologies provides for their effortless integration into a comprehensive and mobile system for ISF analysis, accomplished by preloading the hose with custom sensing papers designed to detect specific analytes. Moreover, the design and functionality of this integrated VT-MAP system are intuitively user-friendly, eliminating the requirement for specialized medical expertise. This feature enhances its potential to make a significant impact on the field of decentralized personal healthcare.

Multi-Sensor Origami Platform: A Customizable System for Obtaining Spatiotemporally Precise Functional Readouts in 3D Models.

Bioprinting technology offers unprecedented opportunities to construct in vitro tissue models that recapitulate the 3D morphology and functionality of native tissue. Yet, it remains difficult to obtain adequate functional readouts from such models. In particular, it is challenging to position sensors in desired locations within pre-fabricated 3D bioprinted structures. At the same time, bioprinting tissue directly onto a sensing device is not feasible due to interference with the printer head. As such, a multi-sensing platform inspired by origami that overcomes these challenges by "folding" around a separately fabricated 3D tissue structure is proposed, allowing for the insertion of electrodes into precise locations, which are custom-defined using computer-aided-design software. The multi-sensing origami platform (MSOP) can be connected to a commercial multi-electrode array (MEA) system for data-acquisition and processing. To demonstrate the platform, how integrated 3D MEA electrodes can record neuronal electrical activity in a 3D model of a neurovascular unit is shown. The MSOP also enables a microvascular endothelial network to be cultured separately and integrated with the 3D tissue structure. Accordingly, how impedance-based sensors in the platform can measure endothelial barrier function is shown. It is further demonstrated the device's versatility by using it to measure neuronal activity in brain organoids.

Minimal-Invasive 3D Laser Printing of Microimplants in Organismo.

Multi-photon 3D laser printing has gathered much attention in recent years as a means of manufacturing biocompatible scaffolds that can modify and guide cellular behavior in vitro. However, in vivo tissue engineering efforts have been limited so far to the implantation of beforehand 3D printed biocompatible scaffolds and in vivo bioprinting of tissue constructs from bioinks containing cells, biomolecules, and printable hydrogel formulations. Thus, a comprehensive 3D laser printing platform for in vivo and in situ manufacturing of microimplants raised from synthetic polymer-based inks is currently missing. Here, a platform for minimal-invasive manufacturing of microimplants directly in the organism is presented by one-photon photopolymerization and multi-photon 3D laser printing. Employing a commercially available elastomeric ink giving rise to biocompatible synthetic polymer-based microimplants, first applicational examples of biological responses to in situ printed microimplants are demonstrated in the teleost fish Oryzias latipes and in embryos of the fruit fly Drosophila melanogaster. This provides a framework for future studies addressing the suitability of inks for in vivo 3D manufacturing. The platform bears great potential for the direct engineering of the intricate microarchitectures in a variety of tissues in model organisms and beyond.

Development of a low-cost robotized 3D-prototype for automated optical microscopy diagnosis: An open-source system.

In a clinical context, conventional optical microscopy is commonly used for the visualization of biological samples for diagnosis. However, the availability of molecular techniques and rapid diagnostic tests are reducing the use of conventional microscopy, and consequently the number of experienced professionals starts to decrease. Moreover, the continuous visualization during long periods of time through an optical microscope could affect the final diagnosis results due to induced human errors and fatigue. Therefore, microscopy automation is a challenge to be achieved and address this problem. The aim of the study is to develop a low-cost automated system for the visualization of microbiological/parasitological samples by using a conventional optical microscope, and specially designed for its implementation in resource-poor settings laboratories. A 3D-prototype to automate the majority of conventional optical microscopes was designed. Pieces were built with 3D-printing technology and polylactic acid biodegradable material with Tinkercad/Ultimaker Cura 5.1 slicing softwares. The system's components were divided into three subgroups: microscope stage pieces, storage/autofocus-pieces, and smartphone pieces. The prototype is based on servo motors, controlled by Arduino open-source electronic platform, to emulate the X-Y and auto-focus (Z) movements of the microscope. An average time of 27.00 ± 2.58 seconds is required to auto-focus a single FoV. Auto-focus evaluation demonstrates a mean average maximum Laplacian value of 11.83 with tested images. The whole automation process is controlled by a smartphone device, which is responsible for acquiring images for further diagnosis via convolutional neural networks. The prototype is specially designed for resource-poor settings, where microscopy diagnosis is still a routine process. The coalescence between convolutional neural network predictive models and the automation of the movements of a conventional optical microscope confer the system a wide range of image-based diagnosis applications. The accessibility of the system could help improve diagnostics and provide new tools to laboratories worldwide.

Low-cost and sustainable smartphone-based tissue-on-chip device for bioluminescence biosensing.

Several organ-on-chip and cell-on-chip devices have been reported, however, their main drawback is that they are not interoperable (i.e., they have been fabricated with customized equipment, thus cannot be applied in other facilities, unless having the same setup), and require cell-culture facilities and benchtop instrumentation. As a consequence, results obtained with such devices do not generally comply with the principles of findability, accessibility, interoperability, and reusability (FAIR). To overcome such limitation, leveraging cost-effective 3D printing we developed a bioluminescent tissue on-a-chip device that can be easily implemented in any laboratory. The device enables continuous monitoring of cell co-cultures expressing different bioluminescent reporter proteins and, thanks to the implementation of new highly bioluminescent luciferases having high pH and thermal stability, can be monitored via smartphone camera. Another relevant feature is the possibility to insert the chip into a commercial 24-well plate for use with standard benchtop instrumentation. The suitability of this device for 3D cell-based biosensing for monitoring activation of target molecular pathways, i.e., the inflammatory pathway via nuclear factor kappa-B (NF-κB) activation, and general cytotoxicity is here reported showing similar analytical performance when compared to conventional 3D cell-based assays performed in 24-well plates.

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.

The Use of Bio-Inks and the Era of Bioengineering and Tooth Regeneration

Abstract Objective: To review existing literature and provide an update on the current use of Bio-Inks and potential future use. Material and Methods: A MeSH keyword search was conducted to find out relevant articles for this short review. Results: Bio inks used in 3D printing grafting require various properties essential for the selection. Combining multiple methods and improved properties is essential for developing successful bio-inks for 3D grafting of functional tissues and tooth pulp regeneration from stem cells. To date, researchers have made many efforts to grow teeth based on stem cells and inculcate regeneration of teeth along with surrounding tissues like alveolar bones and periodontal ligaments. Conclusion: 3D printing with Bio-Inks requires strict adherence to safety protocols for successful outcomes, making it difficult to employ this routinely.

Uso de máquinas 3D e cortadores a laser em simulação aplicada à educação médica / Use of 3D printers and laser cutters for simulation in medical education

Introdução: As impressões tridimensionais (3D) têm obtido relevância em diversas áreas do conhecimento, especialmente na medicina. Com o advento da tecnologia, cada vez mais escolas médicas têm adotado o uso de prototipagem de estruturas humanas para aprimorar o treinamento dos estudantes, uma vez que a simulação produz um ambiente livre de riscos, no qual os alunos podem dominar com sucesso as habilidades relevantes para a prática clínica.Métodos: O projeto foi estruturado a partir da pesquisa dos softwares de impressão; seleção dos segmentos anatômicos a serem impressos; análise de materiais para a confecção; estudo aprofundado das caixas de simulação usadas no treinamento em videocirurgia e, por fim, realização de um treinamento dos estudantes interessados no desenvolvimento das habilidades cirúrgicas.Resultados: Por meio da impressão 3D,foram confeccionadas peças anatômicas para o ensino em anatomia, além de peças de silicone para treinamento de suturas manuais e videolaparoscópicas. O cortador a laser foi utilizado para fabricar caixas pretas, principalmente para simulações de cirurgia laparoscópica.Conclusão: A utilização de materiais 3D no ensino médico tem se mostrado altamente promissora, com aumento da curva de aprendizado dos alunos envolvidos e ótima relação custo-benefício. Contudo, o acesso a essa tecnologia ainda é restrito no Brasil, o que dificulta a expansão do método para todas as escolas médicas nacionais.

Introduction: Three-dimensional (3D) printing has become relevant in several areas of knowledge, especially Medicine. With the advent of technology, medical schools started using prototypes of human structures to improve student training, given that simulation provides a risk-free environment where students can successfully master relevant skills for clinical practice.Methods: The present study consisted of research about printing software, selection of anatomical segments for printing, analysis of printing materials, study of simulation boxes used in video-assisted surgery training, and training of students interested in developing surgical skills.Results: 3D printing was used to fabricate anatomical models for teaching anatomy and silicone models for manual and video-assisted laparoscopic suture training. Laser cutters were used to manufacture black boxes, mainly for laparoscopy simulation. Conclusion: The use of 3D printing in medical education is highly promising, with an improved learning curve among students and an excellent benefit-cost ratio. However, access to this technology is still limited in Brazil, which makes it difficult to expand the method to all national medical schools.

Evaluation of customized peripheral sealing device acceptance for surgical/medical masks among dental professionals during early COVID-19 pandemic / Evaluación de la aceptación de dispositivos de sellado periférico personalizados para máscaras quirúrgicas/médicas entre dentistas durante la pandemia temprana de COVID-19

Abstract A 3-dimensional (3D) printed custom-frame can improve the peripheral seal of readily available surgical/medical masks. This study aimed to assess the acceptance of a 3D-printed custom-frame with the American Society for Testing and Materials (ASTM) surgical/medical masks and the use of a face shield. A total of 206 subjects from a dental school participated, who answered a multiple-choice questionnaire. Participants received an invitation through the institutional email of the school via Qualtrics platform. 3D printed custom-frames were fabricated for each participant. According to their response, participants were divided into 4 groups: mask only (M), mask and frame (MF), mask and face shield (MFS), and all 3 personal protective equipment (MFFS). Data was analyzed in absolute and relative frequency. The acceptance of a 3D-printed custom-frame in the group MFFS varied between ''poor''/''very poor'' (44.7%). It allowed ''good'' performance of routine procedures (40.3%), but ''poor'' visual quality (48.1%). Musculoskeletal tolerance and ease to perform movements were adequate. There was no interference in olfactory sensitivity (44.7%) or in the ability to breathe (34.5%). Finally, it showed "moderate pain" (48.1%) on the ear and "no pain" (38.9%) on the head. The 3D-printed custom-frame adapted to ASTM surgical/medical face masks showed reasonable tolerance. Side effects of ear pain ranging in degrees were noted. Further research is indicated to evaluate safety, comfort, compliance, side effects, and occupational hazards of long-term use of enhanced PPE recommendations.Avoiding the recurrent outbreaks of COVID-19, the use of PPE by the public is necessary. Improper PPE use is a major source of concern for human and environmental health. Preventing such activities can be done by following steps involved in PPE disposals or by getting a new way to re-use such as improving peripherical sealing. Our work highlights that a custom-frame can improve protection, without adverse effects.

Resumen El sellado periférico de las máscaras médicas/quirúrgicas puede ser mejorado fácilmente mediante un marco personalizado impreso en 3 dimensiones (3D). Este estudio tuvo como objetivo evaluar la aceptación de un marco personalizado impreso en 3D cuando usado en combinacion con máscaras médicas/quirúrgicas de la Sociedad Estadounidense para Pruebas y Materiales (ASTM) asi como con el uso de protector facial. Participaron un total de 206 sujetos de una facultad de odontología, quienes respondieron un cuestionario de opción múltiple. Los participantes recibieron una invitación a través del correo institucional de la escuela a través de la plataforma Qualtrics. Se fabricaron marcos personalizados impresos en 3D para cada participante. Según su respuesta, los participantes se dividieron en 4 grupos: solo máscara (M), máscara y marco (MF), máscara y protector facial (MFS) y los 3 equipos de protección personal (MFFS). Los datos se analizaron en frecuencia absoluta y relativa. La aceptación de un marco personalizado impreso en 3D en el grupo MFFS varió entre ''pobre''/''muy pobre'' (44,7%). Permitió un ''buen'' desempeño de los procedimientos de rutina (40,3%), pero una ''mala'' calidad visual (48,1%). La tolerancia musculoesquelética y la facilidad para realizar movimientos fueron adecuadas. No hubo interferencia en la sensibilidad olfativa (44,7%) ni en la capacidad de respirar (34,5%). Finalmente, mostró "dolor moderado" (48,1%) en el oído y "sin dolor" (38,9%) en la cabeza. El marco personalizado impreso en 3D adaptado a las máscaras faciales quirúrgicas/ médicas de ASTM mostró una tolerancia razonable. Se observaron efectos secundarios de dolor de oído que variaron en grados. Estudios futuros deben evaluar la seguridad, la comodidad, efectos secundarios y los riesgos laborales del uso a largo plazo para este tipo de combinación. Para evitar los brotes recurrentes de COVID-19, es necesario el uso de equipamento personal de protección (EPP) por parte del público. El uso inadecuado de EPP es una fuente importante de preocupación para la salud humana y ambiental. La prevención de tales actividades se puede hacer siguiendo los pasos involucrados en la eliminación de EPP o obteniendo una nueva forma de reutilización, como mejorar el sellado periférico. Nuestro trabajo resalta que un marco personalizado puede mejorar la proteccion, sin afectos adversos.

Three-dimensional printing of orbital computed tomography scan images for use in ophthalmology teaching / Impressão tridimensional de imagens médicas de tomografia computadorizada para uso no ensino de oftalmologia

ABSTRACT Introduction: The use of tridimensional (3D) printing in healthcare has contributed to the development of instruments and implants. The 3D printing has also been used for teaching future professionals. In order to have a good 3D printed piece, it is necessary to have high quality images, such as the ones from Computerized Tomography (CT scan) exam, which shows the anatomy from different cuts and allows for a good image reconstruction. Purpose: To propose a protocol for creating digital files from computerized tomography images to be printed in 3D and used as didactic material in the ophthalmology field, using open-source software, InVesalius®, Blender® and Repetier-Host©. Methods: Two orbit CT scan exam images in the DICOM format were used to create the virtual file to be printed in 3D. To edit the images, the software InVesalius® (Version 3.1.1) was used to delimit and clean the structure of interest, and also to convert to STL format. The software Blender® (Version 2.80) was used to refine the image. The STL image was then sent to the Repetier-Host© (Version 2.1.3) software, which splits the image in layers and generates the instructions to print the piece in the 3D printer using the polymer polylactic acid (PLA). Results: The printed anatomical pieces printed reproduced most structures, both bone and soft structures, satisfactorily. However, there were some problems during printing, such as the loss of small bone structures, that are naturally surrounded by muscles due to the lack of support. Conclusion: Despite the difficulties faced during the production of the pieces, it was also possible to reproduce the anatomical structures adequately, which indicates that this protocol of 3D printing from medical images is viable.

RESUMO Introdução: O uso de impressão em 3-D na área da saúde tem contribuído para o desenvolvimento de instrumentos e próteses. A impressão 3-D tem sido usada para o ensino de futuros profissionais. Para se alcançar uma boa peça em 3-D, é necessário ter imagens de alta qualidade, como aquelas geradas pelo exame de Tomografia Computadorizada (TC), que mostra a anatomia sob diferentes cortes e permite uma boa reconstrução de imagem. Objetivo: Propor um protocolo para a criação de arquivos digitais a partir de imagens de tomografia computadorizada a serem impressas em 3-D e usadas como modelo de material didático oftalmológico usando software de código aberto, InVesalius®, Bender® e Repetier-Host©. Métodos: Foram utilizadas imagens em formato DICOM provenientes de dois exames de tomografia computadorizada de órbitas para a impressão tridimensional. Para manuseio das imagens, foram utilizados o InVesalius®, versão 3.1.1, para delimitar e limpar a estrutura de interesse e também para converter em formato STL. O Blender®, versão 2.80 foi usado para refinamento. A imagem em STL foi então enviada para o programa Repetier-Host, versão 2.1.3, que divide a imagem em camadas e gera as instruções para impressão da peça em ácido polilático na impressora tridimensional. Resultados: As peças anatômicas impressas reproduziram de forma satisfatória a maioria das estruturas ósseas e musculares. No entanto, houve dificuldade durante a impressão das estruturas ósseas menores, como perda de estrutura óssea pequena, que não possuíam sustentação, por serem envoltas pelo músculo. Conclusão: Apesar das dificuldades encontradas na produção dessas peças de estudo, foi possível reproduzir estruturas com fidelidade, indicando que o protocolo proposto viabiliza a impressão de imagens oriundas da tomografia computadorizada para impressão tridimensional.

Impresión 3D de modelos estereolitográficos con protocolo abierto / 3D Printing of Stereolithographic Models with Open Protocol

RESUMEN: Se realizó un estudio descriptivo y exploratorio con el objetivo de proponer y validar un protocolo abierto para hacer impresiones 3D de modelos estereolitográficos, que esté a disposición de profesionales en el área de la Odontología. Se capacitó mediante sesiones teórico prácticas, a nueve personas operadoras (estudiantes de último año de la carrera de Odontología), sin previa experiencia en el uso de software y hardware para impresión 3D, divididos en dos grupos; el A trabajó con tres tomografías helicoidales (TAC) y el B con tres Tomografías Computarizadas de Haz Cónico (CBCT), todas en formato DICOM, convertidas en archivos STL. En total se aplicó el protocolo en 99 estructuras óseas correspondientes a 33 mandíbulas, 33 axis y 33 macizos faciales-bases de cráneo, y se imprimieron un total de 33 mandíbulas en filamento PLA (ácido poliláctico). Al finalizar el estudio, no se encontró diferencia estadísticamente significativa en la implementación del protocolo propuesto entre los operadores, las mediciones de las piezas impresas por cada uno de ellos, el patrón de oro, la TAC y el CBCT, con lo cual no solo se validó el protocolo, sino que se logró determinar los recursos necesarios para realizar este tipo de impresiones 3D.

ABSTRACT: A descriptive and exploratory study was carried out with the aim of proposing and validating an open protocol for making 3D impressions of stereolithographic models, which is available to professionals in the area of Dentistry. Nine operators (senior students of the Dentistry degree), without previous experience in the use of software and hardware for 3D printing, divided into two groups were trained through theoretical and practical sessions. The A worked with three helical tomographies (TAC) and the B with three cone beam computed tomography (CBCT), all in DICOM format, converted to STL files. In total, 99 bone structures corresponding to 33 jaws, 33 axis and 33 facial masses-skull bases were analyzed, and a total of 33 jaws were printed in PLA (polylactic acid filament). At the end of the study, no statistically significant difference was found in the implementation of the proposed protocol between the operators, the measurements of the pieces printed by each of them, the gold standard, the TAC and the CBCT, with which not only validated the protocol, but it was possible to determine the resources necessary to carry out this type of 3D printing.

Clinical Applications of Additive Manufacturing Models in Neurosurgery: a Systematic Review

Introduction Three-dimensional (3D) printing technologies provide a practical and anatomical way to reproduce precise tailored-made models of the patients and of the diseases. Those models can allow surgical planning, besides training and surgical simulation in the treatment of neurosurgical diseases. Objective The aim of the present article is to review the scenario of the development of different types of available 3D printing technologies, the processes involved in the creation of biomodels, and the application of those advances in the neurosurgical field. Methods We searched for papers that addressed the clinical application of 3D printing in neurosurgery on the PubMed, Ebsco, Web of Science, Scopus, and Science Direct databases. All papers related to the use of any additivemanufacturing technique were included in the present study. Results Studies involving 3D printing in neurosurgery are concentrated on threemain areas: (1) creation of anatomical tailored-made models for planning and training; (2) development of devices and materials for the treatment of neurosurgical diseases, and (3) biological implants for tissues engineering. Biomodels are extremely useful in several branches of neurosurgery, and their use in spinal, cerebrovascular, endovascular, neuro-oncological, neuropediatric, and functional surgeries can be highlighted. Conclusions Three-dimensional printing technologies are an exclusive way for direct replication of specific pathologies of the patient. It can identify the anatomical variation and provide a way for rapid construction of training models, allowing the medical resident and the experienced neurosurgeon to practice the surgical steps before the operation.

3D printing of canine hip dysplasia: anatomic models and radiographs / Impressão 3D da displasia coxofemoral canina: modelos anatômicos e radiografias

Canine Hip Dysplasia (CHD) is a highly prevalent articular pathological condition. In this sense, radiography becomes an important diagnostic method to determine the presence and severity of the disease. The objective was to create 3D models and their respective radiographs representing the CHD (3D AMCHD). The research was carried out in the Laboratory of 3D Educational Technologies of UFAC, under no. 23107.007273/2017-49 (CEUA/UFAC). A canine skeleton (hip bone, femurs and patellae) was used without anatomical deformities compatible with DCF (pelvis, femurs and patella), which were scanned in order to obtain the files of the base model. In these files the deformations representing the different degrees of CHD were performed. Subsequently, the 3D AMCHD files were printed, mounted and X-rayed. The 3D AMCHD represented the bone deformations of the different degrees of CHD. In the radiographs of the 3D AMCHD it was possible to observe and determine each of the bones that constituted the hip joints. This allowed to reproduce the correct positioning to represent the CHD diagnosis and establish the precise points to determine the Norberg angle. In this way, it was evidenced that the 3D AMCHD can be a possible tool to be used in the Teaching of Veterinary Medicine.(AU)

A displasia coxofemoral canina (DCF) é uma condição patológica articular de grande prevalência. Nesse sentido, a radiografia torna-se um método de diagnóstico importante para determinar a presença e a gravidade da doença. O objetivo do presente trabalho foi criar modelos 3D e suas respectivas radiografias representando a DCF (MADCF 3D). A pesquisa foi realizada no Laboratório de Tecnologias Educacionais 3D da UFAC, sob o nº. 23107.007273/2017-49 (Ceua/Ufac). Foram utilizados esqueletos caninos (pelve, fêmures e patelas) sem deformidades anatômicas compatíveis com a DCF, os quais foram digitalizados a fim de se obterem os arquivos do modelo base. Nesses arquivos foram realizadas as deformações que representavam os diferentes graus da DCF. Posteriormente, os arquivos dos MADCF 3D foram impressos, montados e radiografados. Os MADCF 3D representaram as deformações ósseas dos diferentes graus da DCF. Nas radiografias dos MADCF 3D, foi possível observar e determinar cada um dos ossos que constituíam as articulações coxofemorais. Isso permitiu reproduzir o posicionamento correto para representação do diagnóstico DCF e estabelecer os pontos precisos para determinar o ângulo de Norberg. Dessa forma, evidenciou-se que os MADCF 3D podem ser uma possível ferramenta a ser empregada no ensino de medicina veterinária.(AU)

Using a 3D printer in cardiac valve surgery: a systematic review

SUMMARY BACKGROUND: The use of the 3D printer in complex cardiac surgery planning. OBJECTIVES: To analyze the use and benefits of 3D printing in heart valve surgery through a systematic review of the literature. METHODS: This systematic review was reported following the Preferred Reporting Items for Systematic Review and registered in the Prospero (International Prospective Register of Systematic Reviews) database under the number CRD42017059034. We used the following databases: PubMed, EMBASE, Scopus, Web of Science and Lilacs. We included articles about the keywords "Heart Valves", "Heart Valve Prosthesis Implantation", "Heart Valve Prosthesis", "Printing, Three-Dimensional", and related entry terms. Two reviewers independently conducted data extraction and a third reviewer solved disagreements. All tables used for data extraction are available at a separate website. We used the Cochrane Collaboration tool to assess the risk of bias of the studies included. RESULTS: We identified 301 articles and 13 case reports and case series that met the inclusion criteria. Our studies included 34 patients aged from 3 months to 94 years. CONCLUSIONS: Up to the present time, there are no studies including a considerable number of patients. A 3D-printed model produced based on the patient enables the surgeon to plan the surgical procedure and choose the best material, size, format, and thickness to be used. This planning leads to reduced surgery time, exposure, and consequently, lower risk of infection.

RESUMO INTRODUÇÃO: A impressora 3D é utilizada como coadjuvante no planejamento de cirurgias de cardiopatias complexas. OBJETIVOS: Analisar o uso e os benefícios da impressão 3D em cirurgias de válvula cardíaca por meio de revisão sistemática da literatura. MÉTODOS: Esta revisão sistemática foi conduzida de acordo com os itens do Preferred Reporting for Systematic Reviews e registrada no banco de dados Prospero (Registro Prospectivo Internacional de Revisão Sistemática) sob o número CRD42017059034. Foram utilizados os seguintes bancos de dados: PubMed, Embase, Scopus, Web of Science e Lilacs. Incluídos artigos com os termos de busca "Heart Valves", "Heart Valve Prosthesis Implantation", "Heart Valve Prosthesis", "Printing, Three-Dimensional" e termos relacionados. Dois revisores independentes conduziram a extração dos dados e um terceiro (revisor) solucionou as discordâncias. Todas as tabelas usadas para a extração de dados estão disponibilizadas em site próprio. A ferramenta Cochraine Collaboration foi utilizada para avaliar o risco de viés na inclusão de estudos. RESULTADOS: Identificados 301 artigos e 13 relatos de casos e séries de casos que atenderam aos critérios de inclusão. A amostra envolveu 34 pacientes, com idade de 3 meses a 94 anos. CONCLUSÃO: Até o presente momento, não há estudos que contemplem um número considerável de pacientes. A impressão de um modelo 3D produzida a partir do protótipo do paciente permitirá ao cirurgião planejar a cirurgia, bem como escolher o melhor material, tamanho, formato e espessura da válvula a ser utilizada. Esse planejamento reduz o tempo de cirurgia, a exposição e, consequentemente, a redução do risco de infecção.

Implantología digital con guías quirúrgicas 3D / Digital implantology with 3D surgical guides

Se utilizaron métodos digitales de fabricación para guías quirúrgicas de restricción absoluta, para la colocación asistida de implantes dentales que facilitaron la predicción y planificación de la rehabilitación protética virtual a través de protocolos de CAD-CAM con impresoras 3D de escritorio, aditivas, de bajo costo-eficiencia, obteniendo exactitud controlada y alta precisión, lo que permitió reproducibilidad y predecibilidad implantológica. Con el fin de universalizar, promover y difundir el uso de la tecnología 3D como herramienta facilitadora que la práctica dental actual requiere, se investigó la desviación entre la posición planeada y la final encontrada de los implantes colocados bajo asistencia guiada, dando como resultado una discrepancia clínicamente insignificante que sugiere que la guía quirúrgica en impresoras 3D puede ser utilizada como herramienta clínica para posicionar adecuadamente los implantes dentales.