Evaluación de Protocolos de Autotrasplante Dental Guiado y sus Tasas de Supervivencia y Éxito. Una Revisión Sistemática

Actualmente los factores que influyen en la supervivencia de los dientes trasplantados han podido ser controlados con el uso de la tecnología. El autotrasplante dental guiado ha logrado más predictibilidad y eficiencia, además, h a reducido los tiempos de transferencia desde la extracción hasta el trasplante. El objetivo de esta revisión es describir los protocolos de autotrasplante dental guiado, sus tasas de supervivencia y éxito publicados en la literatura actual. Esta revisió n fue realizada siguiendo la pauta PRISMA. La búsqueda se realizó en MEDLINE, Google Académico, ScienceDirect y SciELO, con los términos "autotransplant", "autotransplantation", "autotransplanting", "dental", "tooth", "teeth", "guided", "guide" con filtro de publicación de 10 años. Se realizó evaluación de riesgo de sesgo mediante pautas Joanna Briggs Institute (JBI) a los estudios, incluyendo en esta revisión sólo con riesgo medio y bajo. Los datos de cada artículo se tabularon en una tabla realizada en el procesador de texto en línea "Google Docs". Diez estudios cumplieron los criterios mencionados y fueron incluidos. Fueron evaluados un total de 37 pacientes entre 9 a 64 años. Los dientes donantes más frecuentes fueron premolares y terceros molares. En la mayoría de los casos los pacientes se encontraban sin antecedentes mórbidos de relevancia. El éxito fue evaluado mediante diversos criterios clínicos y radiográficos. Por otro lado, la supervivencia fue evaluada durante los seguimientos respecto a la permanencia del diente en boca. Este tipo de tratamiento no es muy conocido y los estudios incluidos fueron escasos, por otro lado, estos son de bajo nivel de evidencia (reportes de casos y serie de casos). Los protocolos evaluados difieren en algunas características, sin embargo, todos logran altas tasas de supervivencia y éxito. Igualmente, se presentan algunos fracasos, dónde los dientes debieron ser extraídos por movilidad e inflamación.

Currently, the factors that influence the survival of transplanted teeth have been controlled with the use of technology. Guided dental autotransplantation has achieved greater predictability and efficiency, and has also reduced transfer times from extraction to transplantation. The aim of this review is to describe the protocols of guided dental autotransplantation, their survival and success rates published in the current literature. This review was performed following the PRISMA guideline. The search was carried out in MEDLINE, Google Scholar, ScienceDirect and SciELO, with the terms "autotransplant", "autotransplantation", "autotransplanting", "autotransplanting", "dental", "tooth", "teeth", "guided", "guide" with a 10-year publication filter. Studies were assessed for risk of bias using Joanna Briggs Institute (JBI) guidelines, including only medium and low risk studies in this review. The data for each article were tabulated in a table created in the online word processor "Google Docs". Ten studies met the selection criteria and were included. A total of 37 patients between 9 and 64 years of age were evaluated. The most frequent donor teeth were premolars and third molars. In most cases the patients had no relevant morbid history. Success was evaluated by means of various clinical and radiographic criteria. On the other hand, survival was evaluated during the follow-ups with respect to the permanence of the tooth in the mouth. This type of treatment is not very well known, and the studies included were scarce; on the other hand, they are of a low level of evidence (case reports and case series). The evaluated protocols differ in some characteristics, however, all of them achieve high survival and success rates. There are also some failures, where teeth had to be extracted due to mobility and inflammation.

Challenges of computer-assisted orthognathic surgery in clinical application / 口腔疾病防治

@#After years of development, the advantages of computer-assisted orthognathic surgery have been widely recognized. However, the clinical application of this technology is challenging. Each step may generate errors from data acquisition, computer-assisted diagnosis, and computer-assisted surgical design, causing errors to be transferred from the virtual surgical plan to the operation. The accumulation and amplification of errors will affect the final surgical effect. Currently, digital devices, such as intraoral scanners, are being explored for error control, utilizing automation methods and algorithms, and implementing personalized bone positioning methods. Moreover, there are still many problems that have not been fully resolved, such as precise simulation of postoperative soft tissue, functional assessment of mandibular movement, and absorbable internal fixation materials. Fully understanding computer-assisted orthognathic surgery's limitations could provide direction for optimizing existing methods while helping clinicians avoid risks and maximize its advantages to achieve the best outcome. Many emerging and cutting-edge technologies, such as personalized titanium plates, artificial intelligence, and surgical robots, will further promote the development of this discipline. We can expect future optimization of digital orthognathic surgical technology by innovations in automation, intelligence, and personalization.

Clinical application of perforator vessel location guide plate for fibular musculocutaneous flaps / 口腔疾病防治

Objective@#Based on 3D printing technology, explore the precision of a perforator vessel location guide plate for fibular musculocutaneous flaps before the transplantation of fibular osteocutaneous flaps and evaluate its application effects.@*Methods@#This study was reviewed and approved by the ethics committee, and informed consent was obtained from the patients. From May 2019 to October 2022, 14 patients with jaw defects who needed to undergo fibular perforator flap transplantation at the First Affiliated Hospital of Xinjiang Medical University were selected. For the seven patients in the guide plate group, CTA was combined with Mimics software to reconstruct both lower limbs, and the perforator vessel positioning guide for locating perforator vessels was designed; the two ends of the guide plate were designed as fixed ends, with the upper end fixed to the knee joint and the lower end fixed to the ankle joint, and the guide plate was fabricated by a 3D printer. For the seven patients in the control group, a conventional handheld Doppler probe was used for perforator vessel location. The average operation time, bleeding volume, recovery time, deviation of perforator vessel location, postoperative flap-related complications, postoperative donor site shape satisfaction, and lower extremity functional scale (LEFS) score were recorded. SPSS 25.0 software was used for statistical analysis.@*Results@#The average operation time, bleeding volume, recovery time, deviation of perforator vessel location and postoperative donor site shape satisfaction were significantly better in the guide plate group than in the control group (P<0.05); moreover, the differences in postoperative flap-related complications and LEFS scores were not statistically significant (P>0.05).@*Conclusion@#Based on 3D printing technology, fibular musculocutaneous flap perforator vessels can be more accurately located using a guide plate and the knee and ankle as fixed points, and this method can effectively stabilize the guide position, prevent soft tissue offset, and improve positioning accuracy and thus deserves to be generalized.

3D printed Mg-incorporated polycaprolactone scaffolds for repairing rat skull defects / 口腔疾病防治

Objective@#To evaluate the bone repair effect of 3D-printed magnesium (Mg)-loaded polycaprolactone (PCL) scaffolds in a rat skull defect model.@*Methods@#PCL scaffolds mixed with Mg microparticles were prepared by using 3D printing technology, as were pure PCL scaffolds. The surface morphologies of the two scaffolds were observed by scanning electron microscopy (SEM), and the surface elemental composition was analyzed via energy dispersive spectroscopy (EDS). The physical properties of the scaffolds were characterized through contact angle measurements and an electronic universal testing machine. This study has been reviewed and approved by the Ethics Committee. A critical size defect model was established in the skull of 15 Sprague-Dawley (SD) rats, which were divided into the PCL group, PCL-Mg group, and untreated group, with 5 rats in each group. Micro-CT scanning was performed to detect and analyze skull defect healing at 4 and 8 weeks after surgery, and samples from the skull defect area and major organs of the rats were obtained for histological staining at 8 weeks after surgery.@*Results@#The scaffolds had a pore size of (480 ± 25) μm, a fiber diameter of (300 ± 25) μm, and a porosity of approximately 66%. The PCL-Mg scaffolds contained 1.0 At% Mg, indicating successful incorporation of Mg microparticles. The contact angle of the PCL-Mg scaffolds was 68.97° ± 1.39°, indicating improved wettability compared to that of pure PCL scaffolds. Additionally, compared with that of pure PCL scaffolds, the compressive modulus of the PCL-Mg scaffolds was (57.37 ± 8.33) MPa, demonstrating enhanced strength. The PCL-Mg group exhibited the best bone formation behavior in the skull defect area compared with the control group and PCL group at 4 and 8 weeks after surgery. Moreover, quantitative parameters, such as bone volume (BV), bone volume/total volume (BV/TV), bone surface (BS), bone surface/total volume (BS/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N) and bone mineral density (BMD), of skull defects were better than those in the other groups, indicating the best bone regeneration effect. H&E, Goldner, and VG staining revealed more mineralized new bone formation in the PCL-Mg group than in the other groups, and H&E staining of the major organs revealed good biosafety of the material.@*Conclusion@#PCL-Mg scaffolds can promote the repair of bone defects and have clinical potential as a new scaffold material for the repair of maxillofacial bone defects.

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.

Reparación quirúrgica de fracturas de fémur distal con biomodelos impresos 3D / Surgical repair of distal femur fractures with 3D printed biomodels

Introducción: Las fracturas complejas de fémur distal AO/AOT tipo 33C3.3 constituyen un reto para los ortopedistas debido a la dificultad de su tratamiento y las complicaciones asociadas. El planeamiento y procedimiento quirúrgicos emplean placas condilares, pero estas se asocian a la pérdida de la fijación y al colapso de la reducción. Objetivo: Describir la planificación preoperatoria de una fractura de fémur distal AO/AOT 33C3.3 con bioimpresión 3D y reconstrucción por computadora. Presentación del caso: Paciente masculino de 34 años con fractura izquierda conminuta del fémur distal, AO/AOT tipo 33C3.3, por un accidente de tránsito. El planeamiento y el tratamiento quirúrgicos se realizaron exitosamente con la impresión y reconstrucción de biomodelos 3D. Basados en las imágenes tomográficas del paciente, se identificaron los principales fragmentos, la secuencia de reducción, la cantidad y la posición de los implantes a utilizar. Conclusiones: La planificación preoperatoria resulta una etapa de vital importancia en el manejo de fracturas complejas. Las técnicas convencionales pueden optimizarse con la cirugía asistida por computadora y reconstrucción con biomodelos 3D impresos. Esta novedosa propuesta permitirá el adecuado uso de materiales, una óptima secuencia de reducción, mejor estabilidad de la fractura y menor riesgo de complicaciones quirúrgicas(AU)

Introduction: Complex distal femur fractures AO/AOT type 33C3.3 constitute a challenge for orthopedists due to the difficulty of their treatment and associated complications. The surgical planning and procedure use condylar plates; but these are associated with loss of fixation and collapse of the reduction. Objective: To describe preoperative planning for an AO/AOT 33C3.3 distal femur fracture with 3D bioprinting and computer reconstruction. Case report: The case of a 34-year-old male patient is reported. He has comminuted left fracture of the distal femur, AO/AOT type 33C3.3, due to a traffic accident. Surgical planning and treatment were successfully performed with 3D biomodel printing and reconstruction. Based on the patient's tomographic images, the main fragments, the reduction sequence, the number and position of the implants to be used were identified. Conclusions: Preoperative planning is a critically important stage in managing complex fractures. Conventional techniques can be optimized with computer-assisted surgery and reconstruction with 3D printed biomodels. This novel proposal will allow the appropriate use of materials, optimal reduction sequence, better stability of the fracture and lower risk of surgical complications(AU)

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.

Anatomía de la cámara pulpar y sistema de conductos radiculares: Estrategias pedagógicas unarevisión de literatura / Anatomy of the pulp chamber and the root canal system: Pedagogical strategiesAliterature review

Antecedentes: El conocimiento anatómico de la cámara pulpar y del sistema de conductos radiculareses fundamental para el correcto diagnóstico y planificación del tratamiento en endodoncia. Las herramientas pedagógicasdirigidasa los estudiantes de odontologíacomo apoyo en los procesos formativosde la asignatura de endodoncia favorecen la apropiación del conocimiento e identificación de las variantes morfológicas del sistema de conductos radiculares, que permiten al estudiantela integración del conocimiento. Objetivo:Identificar mediante una revisión de la literatura las estrategias pedagógicas que se utilizan para la enseñanza de morfología del sistema de conductos radiculares en endodoncia. Materiales y métodos: Se realizó una búsqueda bibliográfica de estudios originales en las bases de datos Medline (Pubmed), SciELO, Lilacs, Medline (Ovid), Web of science, Scopus, Embase, Google académico, eligiendo estudios publicadosa partir del año 2010 al 2022, para la selección de los artículos definitivos se seleccionaron estudios concernientes a procesos pedagógicos en endodoncia, excluyendo así otros tipos de enfoques en el área de odontología. Resultados: Se identificaron un total de 63 referencias, los cuales fueron analizados y seleccionados16, siendo excluidos 47 por no cumplir los criterios de inclusión. Conclusión: El uso de herramientas pedagógicas virtuales, didácticas y tecnológicas propician un efecto positivo en el estudiante de pregrado de odontología durante el aprendizaje de anatomía de sistemas de conductos radiculares que aumentan la confianza y seguridad al momento de realizar un tratamiento endodóntico en pacientes

Background: Anatomical knowledge of the pulp chamber and the root canal system is essential for correct diagnosis and treatment planning in endodontics. The pedagogical tools aimed at dental students as support in the training processes of the endodontics subject favor the appropriation of knowledge and identification of the morphological variants of the root canal system, which allow the student the integration of knowledge. Objective: To identify, through a review of the literature, the pedagogical strategies used to teach morphology of the root canal system in endodontics. Materials and methods: A bibliographic search of original studies was carried out in the Medline (Pubmed), SciELO, Lilacs, Medline (Ovid), Web of Science, Scopus, Embase, and Google academic databases, choosing studies published from 2010 to 2022. , for the selection of the definitive articles, studies concerning pedagogical processes in endodontics were selected, thus excluding other types of approaches in the area of dentistry. Results: A total of 63 references were identified, 16 of which were analyzed and selected, 47 being excluded for not meeting the inclusion criteria. Conclusion: The use of virtual, didactic and technological pedagogical tools favor a positive effect on the dentistry undergraduate student while learning the anatomy of root canal systems that increase confidence and security when performing endodontic treatment in patients.

Utility of 3d printing in orthopaedic: a systematic review

The use of 3-Dimensional (3D) printing in orthopaedics keeps pace with technical advancements. However, due to its novelty, few research have examined its application. Therefore, our study aimed to assess the utility of 3D printing in orthopaedics use. We conducted a systematic review study during the period of April-May. Article search was conducted in Google Scholar, National Center for Biotechnology Information, Clinical Key, Pubmed, and Science Direct. We included five publications with a total of 99 patients. Our findings indicate that the orthopaedic application and utilization of 3D printing technologies are expanding. Despite the relative paucity of evidence, these findings suggest the utility of 3D printing technology in a variety of intraoperative deformity correction applications.

El uso de la impresión tridimensional (3D) en ortopedia sigue el ritmo de los avances técnicos. Sin embargo, debido a su novedad, pocas investigaciones han examinado su aplicación. Por lo tanto, el estudio tuvo como objetivo evaluar la utilidad de la impresión 3D en el uso ortopédico. Se realizó un estudio de revisión sistemática durante el período de abril a mayo. La búsqueda de artículos se realizó en Google Scholar, National Center for Biotechnology Information, Clinical Key, Pubmed y Science Direct. Se incluyeron cinco publicaciones con un total de 99 pacientes. Nuestros hallazgos indican que actualmente se expanden la aplicación ortopédica y la utilización de las tecnologías de impresión 3D. A pesar de la relativa escasez de evidencia, estos hallazgos sugieren la utilidad de la tecnología de impresión 3D en una variedad de aplicaciones de corrección de las deformidades intraoperatorias.

3D Printing characteristics and mechanical properties of a bio scaffold obtained from a Micro-CT Scan, using the fused deposition modeling technique

The objective is to determine which biopolymer has the best 3D printing characteristics and mechanical properties for the manufacture of a bioscaffold, using the fused deposition printing technique, with models generated from an STL file obtained from a Micro-CT scan taken from a bovine iliac crest bone structure. Through an experimental exploratory study, three study groups of the analyzed biopolymers were carried out with thirteen printed structures of each one. The first is made of 100% PLA. The second, 90B, we added 1g of diatom extract, and the third, 88C, differs from the previous one in that it also contains 1g of calcium phosphate. The 39 printed structures underwent a visual inspection test, which required the fabrication of a gold standard scaffold in resin, with greater detail and similarity to the scanned bone structure. Finally, the structures were subjected to a compressive force (N) to obtain the modulus of elasticity (MPa) and compressive strength (MPa) of each one of them. A statistically significant difference (p=0.001) was obtained in the printing properties of the biomaterial 88C, compared to 90B and pure PLA and the 88C presented the best 3D printing characteristics. In addition, it also presented the best mechanical properties compared to the other groups of materials. Although the difference between these was not statistically significant (p=0.388), in the structures of the 88C biomaterial, values of compressive strength (8,84692 MPa) and modulus of elasticity (43,23615 MPa) were similar to those of cancellous bone in the jaws could be observed. Because of this result, the 88C biomaterial has the potential to be used in the manufacture of bioscaffolds in tissue engineering.

El objetivo es determinar cuál biopolímero presenta las mejores características de impresión 3D y propiedades mecánicas para la fabricación de un bioandamiaje, utilizando la técnica de impresión por deposición fundida, con modelos generados a partir de un archivo en formato STL que se obtuvo de un Micro-CT Scan de una estructura osea de cresta iliaca bovina. Mediante un estudio exploratorio, se realizaron 3 grupos de estudio con trece estructuras impresas de cada uno. El primero, se compone 100% de PLA. El segundo, 90B, se le agrega 1g de extracto de diatomea, y el tercero, 88C, se diferencia del anterior ya que contiene además, 1g de fosfato de calcio. A las 39 estructuras impresas se les realizó una prueba de inspección visual, por lo que se requirió la confección de un patrón de oro en resina, con mayor detalle y similitud a la estructura ósea escaneada. Finalmente, las estructuras fueron sometidas a una fuerza compresiva (N) para la obtención del módulo de elasticidad (MPa) y de la resistencia compresiva (MPa) de cada una de ellas. Se obtuvo una diferencia estadísticamente significativa (p=0,001) en las propiedades de impresión del biomaterial 88C, con respecto al 90B y al PLA puro, presentando las mejores características de impresión 3D. Además, obtuvo las mejores propiedades mecánicas en comparación con los otros grupos de materiales. Aunque la diferencia entre estos no fue estadísticamente significativa (p=0,388), en las estructuras del biomaterial 88C, se pudieron observar valores de resistencia compresiva (8,84692 MPa) y módulo de elasticidad (43,23615 MPa) que son semejantes a los del hueso esponjoso de los maxilares. A razón de este resultado, el biomaterial 88C cuenta con el potencial para ser utilizado en la fabricación de bioandamiajes en la ingeniería tisular.

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.

Guided Endodontic Surgery ? Case Series

This case report describes three cases in which periapical surgeries were carried out using a new surgical endodontic technique by using a three?dimensional (3D) printed template for guided osteotomy and root resection. In Case 1, the data obtained from preoperative CT scan and cast scan were transferred to a surgical planning software. The surgical template was printed using a 3D printer. Using the template, osteotomy and root?end resection were precisely carried out. In Case 2, after CBCT imaging, data were transferred to stereolithography and a 3D model was fabricated. With the help of the 3D model, a template was fabricated using tray material. This guided surgical template minimized the extent of osteotomy and enabled precise targeting of the apex. In Case 3, a preoperative CT scan aided in the fabrication of a surgical 3D template. The template assisted in the precise removal of the overlying cortical bone.

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.

Microleakage of chairside moulded, 3D-printed and milled provisional restorations using a curve-fit approach

Abstract The purpose of this study was to evaluate and measure the microleakage inhibiting quality of provisional restorations manufactured using computer-aided manufacturing, 3D printing, and chairside molded provisional restorative materials. Fifteen provisional restorations each from 3D printed, milled, and chairside molded were manufactured. All restorations were cemented onto sintered zirconia abutment dies and adhered with zinc-oxide non-eugenol temporary cement. Artificial aging was conducted by thermocycling for 800 cycles to simulate 1 month of clinical use. All specimens were submerged in 2% (w/w) methylene blue for 24 hours at 37°C, sectioned, and analyzed digitally for the distance of dye penetration through image analysis. The data were analyzed using the Kruskal-Wallis test with Dunn-Bonferroni post-hoc. Significant differences in dye penetration depth were observed between all groups except milled vs chairside molded. Light microscopy revealed differences in mean cement thickness for 3D printed, milled, and chairside molded of 83.6 µm (1σ = 31.9 µm), 149.1 µm (1σ = 88.7 µm) and 137.9 µm (1σ = 67.2 µm) respectively. Conclusion: 3D printed provisional restorations were found to have the least amount of microleakage compared to milled and chairside molded provisional restorations.

Resumo O objetivo deste estudo foi avaliar e medir a qualidade de inibição de microinfiltração de restaurações provisórias fabricadas usando manufatura assistida por computador, impressão 3D e materiais de restauração provisória moldados no consultório. Foram fabricadas 15 restaurações provisórias impressas em 3D, fresadas e moldadas em consultório. Todas as restaurações foram cimentadas em matrizes de pilar de zircônia sinterizada e aderidas com cimento temporário de óxido de zinco sem eugenol. O envelhecimento artificial foi conduzido por termociclagem por 800 ciclos para simular 1 mês de uso clínico. Todos os espécimes foram submersos em azul de metileno a 2% (p/p) por 24 horas a 37°C, seccionados e analisados digitalmente quanto à distância de penetração do corante por meio de análise de imagem. Os dados foram analisados usando o teste de Kruskal-Wallis com post-hoc de Dunn-Bonferroni. Foram observadas diferenças significativas na profundidade de penetração do corante entre todos os grupos, exceto entre fresado e moldado na cadeira. A microscopia óptica revelou diferenças na espessura média do cimento para as restaurações impressas em 3D, fresadas e moldadas em cadeira de 83,6 µm (1σ = 31,9 µm), 149,1 µm (1σ = 88,7 µm) e 137,9 µm (1σ = 67,2 µm), respectivamente. Conclusão: As restaurações provisórias impressas em 3D apresentaram a menor quantidade de microinfiltração em comparação com as restaurações provisórias fresadas e moldadas no consultório.

Resistência flexural de uma resina para impressão 3D comparada a resinas acrílicas convencionais empregadas para confecção de placas estabilizadoras de mordida / Flexural resistance of 3D printing resin compared to conventional acrylic resins employed to build occlusal bite splints

Introduction: with the technological advance in dentistry, light-polymerized three-dimensional (3D) printing resins had become an alternative for the manufacture of occlusal splint splints. Objective: the present study aimed to analyze the flexural strength of a resin for 3D printing compared to conventional acrylic resins (chemically activated and thermally activated), under the influence of thermocycling. Material and method: 60 specimens were made, which were distributed in six experimental groups (n = 10), according to the resin employed (chemically activated acrylic resin, thermally activated acrylic resin and 3D printing resin) and the treatment received (control and thermocycling). The specimens were submitted to flexural strength by the three-point flexural test. Result: data analysis showed that the material factor (<0.0001) and the thermocycling factor (p = 0.0096) influenced flexural strength, however, the interaction between the two factors did not (p = 0.9728). Conclusion: it was concluded that 3D printing resins presented the lowest flexural resistance to acrylic resins, especially when submitted to thermocycling.

Introdução: com o avanço tecnológico dentro da odontologia, as resinas fotopolimerizáveis para impressão tridimensional (3D) se tornaram uma alternativa para a fabricação de dispositivos interoclusais. Objetivo: o presente trabalho teve como objetivo analisar a resistência flexural de uma resina para impressão tridimensional comparada com resinas acrílicas convencionais (quimicamente ativada e termicamente ativada), sob a influência da termociclagem. Material e método: foram confeccionados 60 corpos de prova, que foram distribuídos aleatoriamente em seis grupos experimentais (n=10), de acordo com a resina utilizada (resina acrílica ativada quimicamente, resina acrílica ativada termicamente e resina para impressão 3D) e com o tratamento recebido (controle e termociclagem). Os corpos de prova foram submetidos ao ensaio de flexão de três pontos para determinação da resistência flexural. Resultado: a análise dos dados demonstrou que o fator material (<0.0001) e o fator termociclagem (p=0.0096) influenciaram a resistência flexural, entretanto, a interação entre os dois fatores não (p=0.9728). Conclusão: deste modo podemos concluir que a resina para impressão 3D apresentou desempenho inferior às resinas acrílicas, especialmente quando submetida a termociclagem.

Accuracy of 3D printing skull under different CT layer thickness / 解剖学报

Objective To compare the measurement differences between the skull 3D printed model and the real specimen under different CT scan slice thicknesses, and to explore the effect of slice thickness on the accuracy of the 3D printed model. Methods Eight normal skull specimens (marked as Nos. f-8) (group N) were used for CT scanning with different slice thicknesses, specifically 0.625 mm (group A),1.25 mm (group B) , and 2.5mm (group C) ,3.75 mm (group D) , and 5 mm (group E) , and then earned out 3D reconstruction and 3D printing respectively, and compared the anatomical reduction degree of the foramen magnum diameter, anterior clinoid distance, and butterfly wing distance of the 3D printed skull model. Results The reduction degree of anatomical structure of 3D printed skull model decreased with the increase of CT slice thickness. There was no significant difference in the accuracy of 3D model among groups A, B and C (P >0.05 ) . There was a high correlation between group A, B and C and group N ( P < 0 .05 ).The size indexes and statistical values of group A, B and C were similar. Conclusion CT slice thickness has a significant effect on the accuracy and reduction of the 3D printed skull model. The 3D printed model with thin slice data (0.625 mm,1.25 mm,2.5 mm) has higher accuracy and less difference.

Research advances of 3D printing in vascularization / 口腔医学

@#As the key to regeneration of oral and maxillofacial tissues such as bone, dental pulp and skin, vascularization has always been the focus of tissue engineering. With the development of three-dimensional (3D) printing in tissue engineering, there are increasing ways to construct vascular structures. However, to achieve the objective of highly simulating vascular structure in morphology and function and promote tissue repair, it is still a major difficulty for 3D bioprinting to construct highly precise and biologically functional simulated vascular structures. This paper summarizes new progress of 3D printing vascular structure, expounds frontier biological manufacturing technologies of vascular and vascularized structure such as suspension printing, coaxial printing, 4D printing, and so on, analyzes its advantages and disadvantages, and discusses its development prospect, in order to provide reference for the application of 3D printing blood vessels in regeneration and repair of oral and maxillofacial tissues.

Current situation and prospect of 3D printing technology in pharmaceutical preparations / 中国药科大学学报

@#With the rapid advancement of science and technology, the application of 3D printing technology for personalized drug manufacturing is becoming increasingly sophisticated.Compared to traditional manufacturing technology, 3D printing can easily customize preparations with specific sizes, shapes and release behaviors for personalized drug use.This review summarizes the principles of several 3D printing technologies commonly used in drug manufacturing, lists the unique advantages and application examples of 3D printing technology for pharmaceutical preparation, analyses the current research status and development trends of the global industry of drug 3D printing, and summarizes the current problems and challenges facing drug 3D printing, aiming to provide some guidance for researchers of 3D printed drugs.

3D printed orthopedic insoles for flatfoot: a systematic review / 中国康复理论与实践

ObjectiveTo review the classification of orthopedic insoles, common techniques of 3D printing orthopedic insoles, common materials and their application for flatfoot. MethodsLiteratures were retrieved from PubMed, Web of Science, CNKI and Wanfang Data from 2012 to 2022, and the relevant contents were summarized. ResultsA total of ten studies were finally included, from 5 countries, involving 290 participants, which published from 2019 to 2022. Orthotic insoles were classified as prefabricated, semi-custom, and custom, while custom ones were classified as traditional custom and 3D printed custom. 3D printed orthotic insoles were often made with selective laser sintering, fused deposition modeling (FDM) and PolyJet printing technologies, and commonly used materials included ethylene-vinyl acetate (EVA), polylactic acid, thermoplastic polyurethane, polyamide, and polypropylene. For flatfoot, 3D printed orthotic insoles could improve plantar pressure, relieve foot pain and the combined use of insole posting could control rearfoot valgus. Conclusion3D printed custom insoles can be made more efficiently and accurately than traditional custom insoles. The printing technologies and materials often chosen for 3D printed orthotic insoles are mainly FDM and EVA. 3D printed orthotic insoles is effective on plantar pressure, comfort and foot movement function of flatfoot.

Corrective effect of 3D printed scoliosis orthoses / 中国康复理论与实践

ObjectiveTo investigate the in-brace and short-term correction of 3D-printed scoliosis orthoses. MethodsFrom July to December 2021, 36 patients with adolescent idiopathic scoliosis from Ninth People's Hospital, Shanghai Jiaotong University School of Medicine were selected to complete full-length radiographs of the spine before and immediately after wearing the orthosis. They wore the orthosis more than 20 hours a day, and took radiographs six months later. Cobb angle was calculated. They were assessed with Chinese version of the Scoliosis Research Society's outcomes instrument 22 (SRS-22) before wearing and six months follow-up. ResultsThe mean Cobb angle was (22.10±6.29)° before wearing, and it was (7.85±10.90)° immediately after wearing (t = 4.775, P < 0.01) and (14.33±0.74)° six months follow-up (t = 4.189, P < 0.01). The score of functional status of SRS-22 increased six months follow-up (Z = -2.676, P < 0.01). The Cobb angle immediately after wearing correlated with the Cobb angle six months follow-up (r = 0.826, P < 0.05). Conclusion3D-printed scoliosis orthoses can correct the scoliosis satisfactorily, in-brace and in short-term.