Novel techniques and future developments in minimally invasive pectus repair.

After the paradigm shift in the treatment of excavated deformities caused by the introduction of the Nuss technique in 1998, several innovative technical modifications and new treatment modalities have radically changed the surgical approach of pectus excavatum in the last couple of years. These new trends attain different topics. On one hand, the use of three-dimensional (3D) printing and implant customization surge as a possibility for a wider audience as 3D printers become available with lower costs. They provide the surgeon with new elements that enable precise planning, simulation, and customized prostheses amidst a tendency to abandon standardization and incorporate personalized medicine. Another topic comprises mandatory sternal elevation, in the continuous search for safety first always. Complete thoracic remodeling as a goal of repair instead of addressing only focal depressions, leaving the upper chest or focal protrusions unresolved. Finally, although the current surgical approach has evolved significantly, many groups still use lateral stabilizers or direct implant fixation with sutures or wires to the ribs. These systems continue to prove unreliable in preventing implant displacement. Fortunately, the bridge technique, described in this review, has come to address this sometimes fatal issue with encouraging results. We provide an updated overview of the latest developments regarding these concepts, related to the current state-of-the-art of the treatment of pectus excavatum.

Partial Shoulder Arthroplasty Guided by Three-dimensional Prototyping.

Three-dimensional (3D) printing technology is a reality in medicine. In Orthopedics and Traumatology, 3D printing guides a precise and tailored surgical treatment. Understanding and disseminating its applicability, use, and outcomes can foster academicism and improve patient care. This is a report of a rare case of a female young adult patient with osteonecrosis of the humeral head due to avascular necrosis developed in early childhood. The treatment was tailored and optimized with 3D printing, which helped determine the steps for partial humeral arthroplasty.

The role of 3D printing in chest wall reconstruction.

Technology is advancing fast, and chest wall surgery finds particular benefit in the broader availability of three-dimensional (3D) reconstruction and printing. An increasing number of reports are being published on the use of these resources in virtual 3D reconstructions of chest walls in computed tomography (CT) scans, virtual surgeries, 3D printing of real-size models for surgical planning, practice, and education, and of note, the manufacture of customized 3D printed implants, changing the fundamental conception from a surgery that fits all, to a surgery for each patient. In this review, we explore the evidence published on simple chest wall reconstruction, including the use of 3D technology to assist in the improvement of the repair of the most frequent chest wall deformities: pectus excavatum and carinatum. Current studies are oriented to the automatization and customization of transthoracic implants, as well as education on real-size models. Next, we investigate the implementation of 3D printing in the repair of complex chest wall reconstruction, comprised of infrequent chest wall deformities such as pectus arcuatum and Poland syndrome. These malformations are very heterogeneous resulting in a high degree of improvisation during the surgical repair. In this setting, 3D technology plays a role in the standardization of a process that contemplates customization, concepts that may seem contradictory. Finally, 3D printing with biocompatible materials is rapidly becoming the first choice for the reconstruction of wide chest wall oncological resections. In this work, we review the first and most important current publications on the subject.

Three-dimensional replica of the temporal bone in the teaching of human anatomy.

PURPOSE: The current study proposes the comparison of the visualization and identification of anatomical details between natural human temporal bone, its respective copy from three-dimensional printing, and the virtual model obtained from CBCT. METHODS: The sample consisted of undergraduate students in Dentistry (Group UE, n = 22), Postgraduate students in Radiology and Imaging (Group P-RI, n = 20), and Postgraduate students in Forensic Odontology (Group P-FO, n = 24). All participants attended a theoretical class on specialized anatomy of the temporal bone and subsequently performed the markings of 10 determined structures. RESULTS: The number of correct identifications was similar in natural bone and printed three-dimensional models in all groups (p > 0.05). The virtual model showed a significantly lower number of correct structures (p < 0.05) in the 3 groups. In general, there were significantly higher percentages of accurate answers among postgraduate students compared to undergraduate students. Most graduate students believed that the printed three-dimensional model could be used to teach anatomy in place of natural bone, while undergraduate students disagreed or were unsure (p < 0.05). Regarding the virtual tomographic image, in all groups, students disagreed or were not sure that its use would be beneficial in replacing natural bone. CONCLUSION: Three-dimensional and virtual models can be used as auxiliary tools in teaching anatomy, complementing practical learning with natural bones.

The influence of filler load in 3D printing resin-based composites.

OBJECTIVE: To evaluate the influence of the barium glass (BG) filler in 3D printing resin-based composites for restorative structures. METHODS: Experimental 3D printing resin-based composites were formulated with UDMA 70%wt, Bis-EMA 20%wt, and TEGDMA 10%wt. Photoinitiators TPO and DFI (2%wt) were used. BG was incorporated at 40%wt and 50%wt. 0%wt BG was used as negative control and the VarseoSmile Crownplus (Bego) was used as a commercial control. Specimens were printed using a 3D printer. Subsequently, specimens were washed and submitted to post-curing with 405 nm at 60ºC for 2 × 20 min at FormCure (FormLabs). 3D printing resin-based composites were evaluated by flexural strength, degree of conversion, softening in solvent, radiopacity, and cytotoxicity against gingival fibroblasts. Data were statistically analyzed using one-way ANOVA (α = 0.05). RESULTS: No significant differences in flexural strength were showed between BG40% (90.5 ± 5,4 MPa), BG50% (102.0 ± 11.7 MPa) and VA (105.2 ± 11.7 MPa). Addition of 40% and 50% of BG showed no influence in the degree of conversion compared to VA (p > 0.05). All groups showed softening in solvent after immersion in ethanol (p < 0.05). All groups showed more than 1mmAl of radiopacity. BG50% showed significantly higher radiopacity (2.8 ± 0.3 mmAl) than other groups (p < 0,05). Cytotoxicity evaluation showed gingival cell viability higher than 80% for all groups. SIGNIFICANCE: Addition of up to 50%wt of barium glass in experimental 3D printing resin-based composites showed promising results for long-term restorative structures.

3D Printing for Left Ventricular Assist Device Exchange: Insights From Real-World Experience.

Left ventricular assist devices (LVADs) are used in end-stage heart failure. Inadequate positioning of the inflow cannula may necessitate replacement of the LVAD. We present the successful use of a three-dimensional printed model used to optimize surgical planning and allow for simulation and training for the LVAD exchange procedure.

Effect of immersion in disinfectants on the color stability of denture base resins and artificial teeth obtained by 3D printing.

PURPOSE: To evaluate the effect of immersion in disinfecting solutions on the color stability of denture base resins and artificial teeth obtained by 3D printing. MATERIALS AND METHODS: Forty discs (15 × 3 mm) were obtained for each group: Lucitone 550 and Cosmos Denture 3D (denture base resins), Duralay and Cosmos TEMP 3D (artificial teeth resins). The discs were immersed in disinfectant solutions: Corega Tabs, 2% chlorhexidine digluconate, 0.25% sodium hypochlorite, and distilled water. Color measurements were obtained with a spectrophotometer before immersion in disinfectants and after the simulated periods of 6 and 12 months. Data (ΔE00 ) were submitted to mixed three-way ANOVA and Bonferroni post-test. RESULTS: For denture base resins, Cosmos Denture 3D showed greater color change regardless of the solution and immersion time. The immersion time of 6 months influenced the color change of the denture base resins regardless of the disinfectant solution. For the artificial teeth resins, the immersion time of 12 months showed a significant color change when compared to 6 months. Cosmos TEMP 3D showed greater color change for all solutions, except for 0.25% sodium hypochlorite. Duralay resin showed greater color change in 2% chlorhexidine, regardless of immersion time. CONCLUSIONS: For denture base resins, the immersion time significantly changed the color regardless of the solution. For artificial teeth resins, Cosmos TEMP 3D showed greater color changes in all solutions when compared to Duralay, except for 0.25% sodium hypochlorite. Chlorhexidine digluconate significantly changed the color of Duralay.

Solutions based on three-dimensional technologies for the practice and teaching of biomedical sciences

Introduction: Three-dimensional printing is one of the technologies that promote change at an economic and social level, and one of the fundamental elements of industry 4.0. It has enormous potential for the future of medicine, establishing itself as a new paradigm. Despite its advantages, its use in our environment is incipient. Objective: To design and develop solutions based on three-dimensional technologies for the teaching and practice of biomedical sciences. Materials and methods: A technological development investigation was carried out between the Center for Assisted and Sustainable Manufacturing of the University of Matanzas and Matanzas University of Medical Sciences, between September 2019 and July 2022. The designs and fabrications were made from the acquisition of computed tomography images, or from a surface scanner, which were then processed, converted into Standard Tessellation Language format, printed, and post-processed. Virtual designs were developed using computer-aided design software. Results: Various solutions were developed including prototypes: biomodels for craniosynostosis repair and anatomical figures, custom cranial prosthesis mold, hand prosthesis, O2 line splitters, tissue scaffolds, syringe gun, face shields, breast prosthesis; autologous restoration mold and tissue expander. Conclusions: In all areas of application of this technology in medicine―except the printing of medicines, in the current context―, it is feasible to obtain solutions in the territory of Matanzas. It is therefore imperative that managers and the medical community in general, begin to acquire awareness, knowledge, and experience to ensure the optimal use of this technology.

Introducción: La impresión tridimensional es una de las tecnologías que promueve el cambio a nivel económico y social, y uno de los elementos fundamentales de la industria 4.0. Asimismo, constituye un enorme potencial para el futuro de la medicina, estableciéndose como un nuevo paradigma. A pesar de sus ventajas, su explotación en nuestro medio es incipiente. Objetivos: Diseñar y desarrollar soluciones basadas en tecnologías tridimensionales para la enseñanza y la práctica de las ciencias biomédicas. Materiales y métodos: Se realizó una investigación colaborativa, de desarrollo tecnológico entre el Centro de Fabricación Asistida y Sostenible de la Universidad de Matanzas y la Universidad de Ciencias Médicas de Matanzas, entre septiembre de 2019 y julio de 2022. Los diseños y fabricaciones se realizaron a partir de la adquisición de imágenes de tomografía computarizada, o desde un escáner de superficie, las que luego se procesaron, se convirtieron en formato Standard Tessellation Language, se imprimieron y posprocesaron. Los diseños virtuales se desarrollaron empleando un software de diseño asistido por computadora. Resultados: Se desarrollaron varias soluciones que incluyen varios prototipos: biomodelos para reparación de craneosinostosis y figuras anatómicas, molde de prótesis craneal personalizada, prótesis de mano, divisores de líneas de O2, andamios tisulares, pistola portajeringas, protectores faciales, prótesis de mama, molde para restauración autóloga y expansor tisular. Conclusiones: En todas las áreas de aplicación de esta tecnología en medicina―salvo en la impresión de medicamentos, en el contexto actual―, es factible obtener soluciones en el territorio de Matanzas. Es un imperativo, pues, que directivos y la comunidad médica en general, comiencen a adquirir conciencia, conocimientos y experiencias para garantizar la utilización óptima de esta tecnología.

Evaluation of surface roughness, wettability and adhesion of multispecies biofilm on 3D-printed resins for the base and teeth of complete dentures

Abstract Studies evaluating the roughness, wettability and microbial adhesion of 3D-printed resins for complete denture bases and teeth are scarce. Objective This study evaluated the surface roughness, wettability and adhesion of multispecies biofilms (Candida albicans, Staphylococcus aureus and Streptococcus mutans) on 3D-printed resins for complete denture bases and teeth compared to conventional resins (heat-polymerized acrylic resin; artificial pre-fabricated teeth). Methodology Circular specimens (n=39; 6.0 mm Ø × 2.0 mm) of each group were subjected to roughness (n=30), wettability (n=30) and biofilm adhesion (n=9) tests. Three roughness measurements were taken by laser confocal microscopy and a mean value was calculated. Wettability was evaluated by the contact angle of sessile drop method, considering the mean of the three evaluations per specimen. In parallel, microorganism adhesion to resin surfaces was evaluated using a multispecies biofilm model. Microbial load was evaluated by determining the number of Colony Forming Units (CFU/mL) and by scanning electron microscopy (SEM). Data were subjected to the Wald test in a generalized linear model with multiple comparisons and Bonferroni adjustment, as well as two-way ANOVA (α=5%). Results The roughness of the conventional base resin (0.01±0.04) was lower than that of the conventional tooth (0.14±0.04) (p=0.023) and 3D-printed base (0.18±0.08) (p<0.001). For wettability, conventional resin (84.20±5.57) showed a higher contact angle than the 3D-printed resin (60.58±6.18) (p<0.001). Higher microbial loads of S. mutans (p=0.023) and S. aureus (p=0.010) were observed on the surface of the conventional resin (S. mutans: 5.48±1.55; S. aureus: 7.01±0.57) compared to the 3D-printed resin (S. mutans: 4.11±1.96; S. aureus: 6.42±0.78). The adhesion of C. albicans was not affected by surface characteristics. The conventional base resin showed less roughness than the conventional dental resin and the printed base resin. Conclusion The 3D-printed resins for base and tooth showed less hydrophobicity and less adhesion of S. mutans and S. aureus than conventional resins.

Impressão 3D na relação médico-paciente, relato de experiência da integração entre ensino, inovação e assistência / 3D printing in the physician-patient relationship, experience report on the integration between education, innovation and care

RESUMO Introdução: Na literatura, diversos artigos apresentam a satisfação dos pacientes e a melhor clareza de entendimento acerca das informações transmitidas pela equipe médica, com o auxílio de peças tridimensionais. A educação e a saúde são práticas inseparáveis e interdependentes, sempre estiveram articuladas, consideradas elementos fundamentais no processo de atuação dos profissionais da saúde. Assim, professores e alunos do curso de Medicina da Universidade Federal de Pernambuco criaram uma extensão universitária, que objetivava o uso de modelos anatômicos, impressos em 3D, para educação dos pacientes do ambulatório de ortopedia e traumatologia. Relato de experiência: Ao longo dos seis meses de projeto, foram assistidos 77 pacientes, e o projeto contou com o trabalho de três professores e 18 alunos da graduação, totalizando 98 pessoas envolvidas no projeto. As ações foram divididas em dois blocos. O primeiro consistiu na capacitação dos alunos. No segundo, os discentes realizavam visitas ao ambulatório, acompanhados por um médico especialista responsável, usavam peças impressas pelos próprios alunos, para orientar os pacientes quanto à sua respectiva condição, e davam orientações sobre a terapêutica valendo-se dessas peças impressas. Discussão: A possibilidade de utilização dessa ferramenta como auxílio na comunicação médica abre um vasto horizonte de aplicação da impressão 3D na educação popular em saúde. Isso, por sua vez, propicia o aperfeiçoamento da promoção da saúde de regiões menos desenvolvidas, uma vez que essa interação entre equipe de saúde e comunidade permite a promoção, a proteção e a recuperação da saúde, a partir de um diálogo horizontal, valorizando e respeitando o usuário do sistema de saúde, de maneira a torná-lo agente e protagonista do processo saúde e doença. Conclusão: Projetos de extensão desse tipo têm um enorme potencial para gerar impactos na medicina, na comunidade acadêmica e na população assistida, sobretudo a menos instruída.

ABSTRACT Introduction: In the literature, several articles demonstrate patient satisfaction and better understanding of the information transmitted by the medical team, with the aid of three-dimensional pieces. Education and health are inseparable and interdependent practices, they have always been articulated, and considered crucial elements in the action process of health professionals. Thus, teachers and students of the medicine course at Universidade Federal de Pernambuco created a university extension project that aimed at the use of anatomical models printed in 3D, for the education of patients in the orthopedics and traumatology outpatient clinic. Experience Report: Over the six months of the project, 77 patients were assisted and the project employed the work of 3 teachers and 18 undergraduate students, totaling 98 people involved in the project. The actions were divided into 2 blocks: the first consisted of training the students and, in the second, the students visited the outpatient clinic, accompanied by a specialist physician in charge and used pieces printed by the students themselves, to guide the patients regarding their respective condition and provided guidance on therapy using these printed pieces. Discussion: the possibility of using this tool as an aid in medical communication opens up a vast horizon of application of 3D printing in health education. This, in turn, favors the improvement of health promotion in less developed regions, since this interaction between the health team and the community allows the promotion, protection and recovery of health, based on a horizontal dialogue, valuing and respecting the users of the health system, aiming to make them an agent and protagonist of the health and disease process. Conclusion: It can be concluded, therefore, that extension projects such as this one have enormous potential to generate impacts on medicine, the academic community and the assisted population, especially the less educated ones.

Desafíos en el empleo de los medicamentos huérfanos

Las enfermedades raras son aquellas que tienen baja prevalencia y que, por lo tanto, el desarrollo de medicamentos para tratarlas no es rentable para las empresas farmacéuticas debido a la baja demanda. A pesar de que ya se cuenta con diferentes políticas públicas alrededor del mundo para incentivar a las industrias farmacéuticas a investigar estos medicamentos, conocidos como medicamentos huérfanos, su desarrollo conlleva muchas dificultades en las evaluaciones clínicas y el precio final para el público es muy elevado. Si bien en años recientes se ha planteado el uso de tecnología de impresión en 3D para producir estos medicamentos o incluso recurrir a otros medicamentos previamente aprobados para tratar enfermedades raras, existe un historial de mal uso de las legislaciones por parte de las empresas con el fin de generar beneficios comerciales, por lo que estas políticas deben reforzarse para que cumplan su propósito; ayudar a una población muy vulnerable. El objetivo del presente texto es exponer los resultados de una revisión documental sobre el panorama científico y sociopolítico en el que se encuentra el problema de las enfermedades raras y los medicamentos huérfanos, así como las posibles soluciones que se están desplegando para abordarlo. Deriva de un estudio que se desarrolla en el momento actual en la Universidad Autónoma Metropolitana, de Ciudad de México.

The strange illnesses are those that have low prevalence and that, therefore, the development of medications to treat them is not profitable for the pharmaceutical companies due to the drop demands. Although it is already counted with different political public around the world to motivate to the pharmaceutical industries to investigate these medications, well-known as orphan medications, their development bears many difficulties in the clinical evaluations and the final price for the public it is very high. Although in recent years he/she has thought about the use of impression technology in 3D to produce these medications or even to appeal to other medications previously approved to treat strange illnesses, a record of wrong use of the legislations exists on the part of the companies with the purpose of generating commercial benefits, for what these politicians should be reinforced so that they complete its purpose; to help a very vulnerable population. The objective of the present text is to expose the results of a documental revision on the scientific and sociopolitical panorama in which is the problem of the strange illnesses and the orphan medications, as well as the possible solutions that they are spreading to approach it. It derives of a study that is developed in the current moment in the Metropolitan Autonomous University, of Mexico City.

Accuracy of models of partially edentulous arches obtained by three-dimensional printing: An in vitro study.

Aim: The aim of this study was to evaluate the accuracy of models of partially edentulous arches obtained by three-dimensional (3D) printing. Settings and Design: This was an in vitro study. Materials and Methods: Fifteen partially edentulous models were evaluated, using two methods of measuring dimensions: virtual, using the Standard Tessellation Language files of the models and software (control group), and physical, through printing the models and digital caliper (test group). For both methods, measurements were made regarding the dimensions of the teeth (width and length - buccal/lingual or palatal/occlusal) and distances between the teeth. Statistical Analysis Used: For the variable of linear measurements (width and length) and distances between teeth of the same hemiarch, the Wilcoxon test was used, while for the variable between opposite hemiarches, the paired t-test was used. Results: In the evaluation of the linear measurements, a significant difference was observed only when the width of the molar tooth was analyzed (P = 0.014). When the buccal length was measured, all teeth had linear measurements provided by the virtual method that was lower than the physical (P = 0.000), as well as the lingual/palatal length in incisors (P = 0.003) and molars (P = 0.009) and in total (P = 0.001). As for the analyses between teeth, no difference was identified between the measurements provided by the virtual method compared to the physical one. Conclusions: The 3D printer used to print partially edentulous models provided linear distortions in the teeth but without changes in the distances between teeth of the same hemiarch and between teeth of opposite hemiarches.

Three-dimensional-printed scaffolds for periodontal regeneration: A systematic review.

Background: As current ethical codes preclude determining whether the clinical improvements obtained with the use of three-dimensional (3D)-printed scaffolds represent true periodontal regeneration, the histological proof of evidence for regeneration must be demonstrated in animal models. Thus, this systematic review investigated the regenerative potential of 3D-printed scaffolds in animal models of periodontal defects. Materials and Methods: A systematic search was performed in four databases (Medline, Embase, Web of Science, and Scopus) to identify preclinical controlled studies that investigated the use of 3D-printed scaffolds for periodontal regeneration. Studies limited to periodontal defects treated with 3D scaffolds were eligible for inclusion. The primary outcome was periodontal regeneration, assessed histologically as new bone, cementum, and periodontal ligament (PDL). This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Quality was assessed according to the SRYCLE score. Results: Six studies met the inclusion criteria. Scaffolds were designed using computer-aided design software. While the absence of a scaffold resulted in defects repaired mainly with fibrous connective tissue, the use of nonguiding 3D scaffolds promoted some bone formation. Notably, the regeneration of cementum and functional PDL fibers perpendicularly inserted into the root surface and the alveolar bone was limited to the defects treated with multi-compartment fiber-guiding or ion-containing 3D scaffolds. Nevertheless, the quality of the evidence was limited due to the unclear risk of bias. Conclusions: Despite the limitations of the available evidence, the current data suggest that the use of printed multi-compartment fiber-guiding or ion-containing 3D scaffolds improves periodontal regeneration in animal models.

Patient-specific airway stent using three-dimensional printing: a review.

The primary function of an airway stent is to reestablish patency, impeding restenosis, supporting the tracheobronchial wall, or occluding fistulas. But stent-related complications are prevalent and can have devastating consequences. For this reason, stents are considered a last resort when there are no alternatives in treatment. Additionally, commercially available airway stents often poorly fit patients with complex airways, and they can cause various complications. At the end of the 20th century, three-dimensional (3D) printing technology was created. It has been transformative in healthcare and has been used in several applications. One of its first utilizations was the anatomical modeling of body structures that helps preoperative planning. In respiratory medicine, this technology has been essentially used in central airway diseases to produce 3D airway models and to create airway splints and prostheses. In the last decade, it has led to a transformation and allowed progress in personalized medicine, making patient-specific stents for individuals with complex airway problems. A patient-specific stent using 3D printing may minimize complications, improve quality of life, and reduce the need for repeated procedures. This review describes the recent advances in 3D printing technology, its use for developing airway prostheses to treat complex airway diseases, and the current evidence that supports its use.

Gradual changes in model shape affect egg-directed behaviours by parasitic shiny cowbirds Molothrus bonariensis in captivity.

Eggs are critically important for avian reproduction as all birds are oviparous. Accordingly, the recognition and care of own eggs represent the cornerstones of avian breeding, whereas the elimination of foreign objects, including brood-parasitic eggs and non-egg items from the nest are known to also increase fitness by refocusing incubation effort on the parents' own eggs. But egg recognition also plays a role in some avian obligate brood parasites' reproductive strategy through the pecking of already present eggs in the hosts' clutch to reduce nestmate competition with the parasite's own hatchling. Here we tested egg shape recognition in this parasitic egg-pecking context by exposing two different series of 3D printed models to captive obligate brood-parasitic shiny cowbirds (Molothrus bonariensis) in artificial nests. Natural egg-shaped models were pecked more often compared with increasingly thinner models, but there was no effect of increasing angularity on pecking rates, implying that a natural, rather than an artificial, range of variability elicited adaptive responses from parasitic cowbirds.

An Innovative 3D Printed Tooth Reduction Guide for Precise Dental Ceramic Veneers.

Tooth reduction guides allow clinicians to obtain the ideal space required for ceramic restorations. This case report describes a novel design (CAD) for an additive computer-aided manufactured (a-CAM) tooth reduction guide with channels that permitted access for the preparation and evaluation of the reduction with the same guide. The guide features innovative vertical and horizontal channels that permit comprehensive access for preparation and evaluation of the reduction with a periodontal probe, ensuring uniform tooth reduction and avoiding overpreparation. This approach was successfully applied to a female patient with non-carious lesions and white spot lesions, resulting in minimally invasive tooth preparations and hand-crafted laminate veneer restorations that met the patient's aesthetic demands while preserving tooth structure. Compared to traditional silicone reduction guides, this novel design offers greater flexibility, enabling clinicians to evaluate tooth reduction in all directions and providing a more comprehensive assessment. Overall, this 3D printed tooth reduction guide represents a significant advancement in dental restoration technology, offering clinicians a useful tool for achieving optimal outcomes with minimal tooth reduction. Future work is warranted to compare tooth reductions and preparation time for this guide to other 3D printed guides.

Efficacy of three-dimensional models for medical education: A systematic scoping review of randomized clinical trials.

To estimate the efficacy of three-dimensional (3D) models for medical education. METHODS: A systematic scoping review was performed containing diverse databases such as SCOPUS, PubMed/MEDLINE, SCIELO, and LILACS. MeSH terms and keywords were stipulated to explore randomized clinical trials (RCTs) in all languages. Solely RCTs that accomplished the eligibility criteria were admitted. RESULTS: Fifteen RCTs including 1659 medical students were chosen. Five RCTs studied heart models, 3 RCTs explored facial, spinal and bone fractures and the rest of the trials investigated eye, arterial, pelvic, hepatic, chest, skull, and cleft lip and palate models. Regarding the efficacy of 3D models, in terms of learning skills and knowledge gained by medical students, most RCTs reported higher scores. Considering the test-taking times, the results were variable. Two RCTs showed less time for the 3D group, another RCT indicated variable results in the response times of the test depending on the anatomical zone evaluated, while another described that the students in the 3D group were slightly quicker to answer all questions when compared with the traditional group, but without statistical significance. The other 11 experiments did not present results about test-taking times. Most students in all RCTs indicated satisfaction, enjoyment, and interest in utilizing the 3D systems, and recognized that their abilities were enhanced. CONCLUSIONS: Higher efficacy in terms of learning skills and knowledge gained was observed when the 3D systems were used by medical students. Undergraduates also expressed great satisfaction with the use of these technologies. Regarding the test-taking times, the results favored the 3D group.

Tubos cerâmicos impressos em 3D: controle rotacional do primeiro molar superior / 3D printed ceramic tubes: rotational control of maxillary first molar

No final da década de 70, ocorreu a introdução da tecnologia de desenho assistido por computador e fabricação assistida por computador (CAD/CAM) na Odontologia. As principais proposições dessa tecnologia seriam automatização do processo manual minimizando as variações ou falhas humanas. Dentre os benefícios do produto citado, destacam-se a possibilidade de individualização dos acessórios de acordo com as necessidades biomecânicas do paciente, personalizando a sua prescrição e o formato da sua base para melhor adaptação ao dente, dando ao ortodontista a possibilidade de alcançar finalizações de tratamentos muito mais precisas. A posição do primeiro molar superior tem grande importância para a clínica ortodôntica. As rotações dos primeiros molares superiores estão presentes na maioria das más oclusões, principalmente na má oclusão de Classe II de Angle Divisão 1, que aumenta o espaço ocupado pelos dentes na arcada dentária. O presente estudo avaliou in vitro o desempenho dos tubos no controle rotacional dos molares superiores. Nesta pesquisa, os tubos foram colados em primeiros molares superiores esquerdos artificiais de resina, aleatoriamente, divididos em quatro grupos, de acordo com o tipo de tubo utilizado e posicionamento de colagem. Os seguintes grupos foram testados: Grupo 1: Tubo cerâmico prototipado, colado na posição central; Grupo 2: Tubo cerâmico prototipado, colado na posição distal; Grupo 3: Tubo simples metálico colado na posição central e Grupo 4:Tubo simples metálico colado na posição distal. Para a execução dos testes, hemiarcadas superiores esquerdas contendo desde o dentes incisivo central superior ao segundo molar superior esquerdo foram obtidas por arquivo STL (Standard Triangle Language) através do software americano Autodesk Meshmixer. Os tubos ortodônticos foram fixados por colagem indireta com cianoacrilato na face vestibular dos dentes. Para a avaliação da eficiência dos tubos ortodônticos na correção da rotação do primeiro molar superior foi necessária a utilização de um simulador eletrônico, com o objetivo de padronizar os testes para todas as amostras pesquisadas. Testes T de student e Mann-Whitney foram aplicados para avaliar diferença estatística entre os resultados obtidos nos grupos. Na posição Central, a média dos pulsos de correção dos tubos cerâmicos prototipados (39.41 pulsos) foi superior à média dos tubos metálicos (27.37 pulsos) (teste T de Student p<0.05). Na posição distal, a média dos pulsos de correção dos tubos cerâmicos prototipados (38.38 pulsos) foi superior à média dos tubos metálicos (18.07 pulsos) (teste de Mann-Whitney, p<0.05). Tubos cerâmicos prototipados obtiveram uma maior intensidade da correção da rotação do molar superior que os tubos metálicos, através da metodologia adotada na presente pesquisa, nas duas situações avaliadas. (AU)

At the end of the 1970s, computer-aided design and computer-aided manufacturing (CAD/CAM) technology was introduced into dentistry. The main propositions of this technology would be the automation of the manual process, minimizing human variations or errors. Among the benefits of the product, the possibility of individualizing the accessories according to the patient's biomechanical needs stands out, customizing their prescription and the shape of their base for better adaptation to the tooth, giving the orthodontist the possibility of achieving complete much more accurate treatments. The position of the upper first molar is of great importance for the orthodontic clinic. Rotations of the upper first molars are present in most malocclusions, especially in Angle Class II Division 1 malocclusion, which increases the space occupied by the teeth in the dental arch. The present study evaluated in vitro the performance of the tubes in the rotational control of upper molars. In this research, the tubes were bonding to artificial resin upper left first molars, randomly, divided into four groups, according to the type of tube used and gluing positioning. The following groups were tested: Group 1: Prototyped ceramic tube, bonded in the central position; Group 2: Prototyped ceramic tube, bonded in the distal position; Group 3: Simple metallic tube bonded in the central position and Group 4: Simple metallic tube bonded in the distal position. For the execution of the tests, upper left hemiarchs containing from central incisor teeth superior to the upper left second molar were obtained using an STL (Standard Triangle Language) file using the American software Autodesk Meshmixer. The orthodontic tubes were fixed by indirect bonding with cyanoacrylate on the buccal surface of the teeth. To evaluate the efficiency of orthodontic tubes in correcting the rotation of the upper first molar, it was necessary to use an electronic simulator, with the aim of standardizing the tests for all samples researched. Student's T and Mann-Whitney tests were applied to evaluate statistical differences between the results obtained in the groups. In the Central position, the average correction pulses for the prototyped ceramic tubes (39.41 pulses) were higher than the average for the metallic tubes (27.37 pulses) (Student's T test p<0.05). In the distal position, the average correction pulses for the prototyped ceramic tubes (38.38 pulses) were higher than the average for the metallic tubes (18.07 pulses) (Mann-Whitney test, p<0.05). Prototyped ceramic tubes obtained a greater intensity of correction of upper molar rotation than metallic tubes, through the methodology adopted in the present research, in the two situations evaluated. (AU)

Aplicación clínica de la Impresión 3D en el manejo de fracturas abiertas de tibia: Nuevas fronteras en Traumatología. Estudio experimental / Clinical application of 3D Printing in open tibial fractures management: New frontiers of Orthopaedics. An experimental study

La Impresión 3D es una tecnología emergente utilizada cada vez más en medicina. En los países en vías de desarrollo, donde las fracturas por motocicletas y automóviles se encuentran en aumento, la disponibilidad de fijadores externos para el manejo de fracturas abiertas es un problema frecuente. La impresión 3D puede ser una alternativa económica e igualmente confiable a los dispositivos tradicionales elaborados con acero o titanio. El objetivo de este trabajo es mostrar la experiencia con el uso de Impresión 3D y su aplicación en el manejo clínico de fracturas abiertas diafisiarias de tibia. Se realizó un estudio pre-experimental y prospectivo. Se incluyeron 14 pacientes con fracturas de tibia AO/ASIF 42A, 42B y 42C tratados con un fijador externo con rótulas elaboradas con Impresión 3D como medida de Control de Daños en Ortopedia desde su ingreso hasta su resolución definitiva. Todos los pacientes fueron de sexo masculino, con un promedio de edad 23,16 años con 50% entre 20-23 años. Las fracturas fueron 42,85% tipo 42A, 37,71% 42B y 21,42% 42C. El 78,57% de las fracturas fueron ocasionadas por motocicletas: 57,14% grado II según Gustilo y Anderson, un 28,57% grado III y 14,28% grado I. El 37,71% eran politraumatizados. Ninguno de los pacientes presentó complicaciones como pérdida de la reducción, aflojamiento de las rótulas, ruptura o fatiga de las rótulas ni fatiga de la barra. La impresión 3D demostró ser una herramienta y alternativa útil en el manejo agudo de fracturas abiertas diafisiarias de tibia(AU)

3D Printing is an emerging technology used more and more in medicine. In developing countries, where motorcycle and automobile fractures are on the rise, the availability of external fixators for the management of open fractures is a frequent problem. 3D printing can be a cheap and equally reliable alternative to traditional devices made of steel or titanium. The objective of this work is to show the experience with the use of 3D Printing and its application in the clinical management of open diaphyseal fractures of the tibia. A pre-experimental and prospective study was made. 14 patients with AO/ASIF tibia fractures 42A, 42B and 42C treated with an external fixator with 3D-printed ball-caps as a Damage Control measure in Orthopedics from admission to final resolution were included. All patients were male, with an average age of 23,16 years, 50% between 20-23 years. The fractures were 42,85% type 42A, 37,71% 42B and 21,42% 42C. 78,57% of the fractures were caused by motorcycles: 57,14% grade II according to Gustilo and Anderson, 28,57% grade III and 14.28% grade I. 37,71% were polytraumatized. None of the patients had complications such as loss of reduction, loosening of the patellas, rupture or fatigue of the patellas, or rod fatigue. 3D printing proved to be a useful tool and alternative in the acute management of open diaphyseal fractures of the tibia(AU)

Three-Dimensional Printing Technologies for Drug Delivery Applications: Processes, Materials, and Effects.

Since the 1930s, new methods of drug delivery, such as implantable devices with drug release control, have been developed. However, manufacturing techniques require bulk due to high initial production costs. Three-dimensional (3D) printing, also known as additive manufacturing or rapid prototyping, allows the fabrication of personalized drug delivery that uses different materials and complex geometries with multiple release profiles, thereby eradicating high initial costs. Different studies have been developed showing the extensive potential of 3D printing for the pharmaceutical industry, and despite in-depth discussions that have been published, there is no comprehensive review of processes, materials, and effects in drug delivery applications thus far. This review aims to fill this gap by presenting the use of 3D printing technology for drug delivery, exposing the different variations of the technique according to the characteristics, material, and dosage form sought. There are seven main categories of 3D printing according to the standards jointly developed by International Organization for Standardization and American Society for Testing and Materials: material jetting, binder jetting, material extrusion, vat photopolymerization, powder bed fusion, sheet lamination, and directed energy deposition. There are different 3D fabrication processes used for drug delivery applications depending on the dosage form and material applied. In this context, polymers, glasses, and hydrogels represent the most frequent materials used. 3D printing allows different forms of drug dosage. Oral, topical, rectal and vaginal, parental and implantable are discussed in this paper, presenting the identification of the type of 3D printing technology, the active pharmaceutical ingredient, formulation, and pharmaceutical effect. The main aim of this paper is to offer insights to people from academy and industry who are interested in the advancement of drug delivery and in knowing the future directions in the development of 3D printing applications in this area.