The development of a didactic model to facilitate the understanding of the components and anatomical relations of the middle ear / O desenvolvimento de um modelo didático para facilitar a compreensão dos componentes e das relações anatômicas da orelha média

The middle ear is important from an anatomical and clinical point of view, seeing that it contains and allows the passages of structures, in addition to establishing relations with other regions of the head. However, the middle ear is small and difficult to dissect, making difficult the study in cadavers and understanding. In this context, professors and students from Universidade Estadual do Oeste do Paraná developed an anatomical model of the middle ear, showing its main bones, membranes, muscles and nerves. The model was developed with acrylic plates joined to form a cube, each side representing one of the middle ear's walls. The tympanic membrane and the secondary tympanic membrane were represented by an elastic fabric, which covered openings on the membranous wall and the labyrinthic wall, respectively. The auditory ossicles, the muscles and the nerves were made from polymer clay and positioned inside the cube, according to their characteristics and anatomical position in the middle ear. Furthermore, the auditory tube was represented by a plastic cone projecting from the carotid wall. The use of these low-cost anatomical models is an alternative to enable and improve learning. These initiatives favor the teaching of Human Anatomy, increasing understanding, the establishment of clinical correlations, and improving the academic education of health professionals (AU)

A orelha média é importante do ponto de vista anatômico e clínico, pois contém e permite a passagem de estruturas, além de estabelecer relações com outras regiões da cabeça. Porém, a orelha média é pequena e dissecação, o que dificulta seu estudo em cadáveres e a compreensão por parte dos alunos. Nesse contexto, docentes e discentes da Universidade Estadual do Oeste do Paraná desenvolveram um modelo anatômico da cavidade timpânica, apresentando seus principais componentes membranáceos, ósseos, musculares e nervosos. Para a confecção da maquete, placas de acrílico transparente foram unidas formando um cubo, com cada placa representando uma das paredes da cavidade timpânica (exceto a parede tegmental). Tecidos elásticos foram colocados em orifícios feitos nas paredes membranácea e labiríntica para representação da membrana timpânica e da membrana timpânica secundária, respectivamente. Os ossículos da audição, músculos e nervos foram confeccionados em biscuit e posicionados no espaço interno do cubo, observando-se as características e a posição anatômica dessas estruturas na orelha média. A tuba auditiva foi representada pela colocação de um cone plástico projetando-se a partir da parede carótica. A confecção de modelos didáticos é uma alternativa de baixo custo para facilitar o ensino e a compreensão da Anatomia Humana. O aprendizado de conceitos básicos favorece o entendimento das correlações anatomoclínicas, melhorando a formação acadêmica dos profissionais de saúde (AU)

Anatomical description and variations of the anterior arterial brain circulation in Colombian cadaveric specimens / Descripción anatómica y variaciones de la circulación cerebral arterial anterior en especímenes cadavéricos colombianos

SUMMARY: Understanding microsurgical neuroanatomy is a fundamental part of the training of neurosurgeons. Notwithstanding the fact that throughout history the study in cadavers has been a fundamental part of training, the publication of these studies has never marked a trend, and in our country the available studies are limited. A descriptive anatomical study was carried out on 22 specimens regarding the anatomical arrangement of the anterior circulation arteries of the brain and the most frequent anatomical variants in the sample used. To this end, bilateral pterional and bifrontal approaches were performed, obtaining a total of 132 arteries, including supraclinoid internal carotid arteries (ICA), anterior cerebral arteries in their A1 segment (ACA), and middle cerebral arteries in their M1 segment (MCA). measurements in each of these segments were made and anatomical variants were documented. Out of 22 cadaveric specimens, 17 (77 %) were male. the mean age was 59 years (range 36-81 years). Internal carotid artery mean length was 12.73 and 12.86 in the right and left side respectively. Anatomical variants identified were hypoplasia of segment A1 in 1 (4.5 %) specimen, duplication in 1 (4.5 %) and trifurcation of segment M1 in 3 (13.6 %) specimens. A similarity was found between our data and data reported by literature, with some differences, especially in the anterior communicating artery.

RESUMEN: Entender la neuroanatomía microquirúrgica es una parte fundamental de la formación de los neurocirujanos. A pesar de que, durante la historia, el estudio en cadáveres ha sido parte fundamental del entrenamiento, no ha sido tendencia la publicación de estos estudios, y en nuestro país son limitados los que se encuentran. Se realizó un estudio descriptivo anatómico en 22 especímenes acerca de la disposición anatómica de las arterias de la circulación cerebral anterior y las variantes anatómicas más frecuentes en población colombiana. Para dicho objetivo se realizaron abordajes bilaterales pterionales, y bifrontales obteniendo un total de 132 arterias incluyendo las arterias carotídeas internas supraclinoideas (ACI), arterias cerebrales anteriores en su segmento A1 (ACA) y las arterias cerebrales medias en su segmento M1 (ACM), se realizaron mediciones en cada uno de estos segmentos y se documentaron las variantes anatómicas. De los 22 especímenes cadavéricos, 17 (77 %) eran masculinos, la edad media fue de 59 años (rango 36-81 años). La longitud media de la arteria carótida interna fue de 12,73 mm en el lado derecho y de 12,86 mm en el lado izquierdo. Las variantes anatómicas identificadas fueron hipoplasia del segmento A1 en 1 (4,5 %), duplicación de A1 en 1 (4,5 %) y trifurcación del segmento M1 en 3 (13,6 %) muestras. Se encontró una similitud entre nuestros datos y los reportados por la literatura, con algunas diferencias, especialmente en el segmento de la arteria comunicante anterior.

Evaluación del Error Dimensional en la Reproducción Tridimensional de una Mandíbula Humana Disecada Mediante Prototipado Rápido de Modelado por Deposición Fundida / Evaluation of the Dimensional Error in the Three-Dimensional Reproduction of a Dissected Human Jaw by Rapid Prototyping of Molten Deposition Modeling

RESUMEN: Las técnicas de prototipado rápido se están utilizando de forma masiva en distintas áreas médicas, siendo de gran utilidad para el manejo preoperatorio y para el ahorro de tiempo clínico en diversos procedimientos quirúrgicos. El propósito de este trabajo fue fabricar un biomodelo mediante impresión 3D utilizando la técnica de modelado por deposición fundida, corroborando que fuese una réplica fiel de una mandíbula humana disecada. Se generó un modelo 3D a partir de la adquisición volumétrica con CBCT de una mandíbula con marcadores craneométricos de referencia y se imprimió utilizando técnica de modelado por deposición fundida. La comparación de ambas mandíbulas se realizó con la medición de las distancias entre los distintos puntos craneométricos, de forma homóloga. No hubo diferencia estadística para los resultados de la comparación entre ambas estructuras, presentando un error dimensional promedio de 0,16 ± 0,11. El modelo obtenido corresponde a una réplica fidedigna de la mandíbula original, permitiendo validar la técnica para posteriores fines clínicos.

ABSTRACT: Rapid prototyping techniques are widely used in different medical areas, being useful for preoperative management and saving clinical time in various surgical procedures. The purpose of this work was the manufacture of a biomodel by the means of 3D printing using the fused deposition modeling technique, proving that it was a faithful replica of a dissected human jaw. A 3D model was generated from the volumetric acquisition with CBCT of a mandible with craniometric reference markers and was printed using fused deposition modeling technique. The comparison of both jaws was made with the measurement of the distances between the different craniometric points, in a homologous way. There was no statistical difference for the results of the comparison between both structures, obtaining an average dimensional error of 0.16 ± 0.11. The manufactured model corresponds to a reliable replica of the original jaw, allowing validation of the technique for later clinical purposes.

Comparação de Diferentes Técnicas de Moldagem com Silicone de Adição - Estudo in vitro / Comparison of Different Impression Techniques With Addition Silicone - in vitro Study

Objetivo: Comparar diferentes técnicas de moldagem com silicone de adição, quanto à precisão e fidelidade da cópia através de medidas manuais e sobreposição em CAD/CAM. Material e método: Foram realizadas 4 moldagens com silicone de adição de um mesmo modelo nas seguintes técnicas: T1 ­ dois passos com recorte; T2 ­ dois passos com alívio de filme PVC; T3 ­ dois passos sem alívio e T4 - simultânea. A fidelidade das 4 técnicas de moldagem foi avaliada por meio de mensurações de 5 dimensões nos modelos de gesso vazados em cada um dos moldes obtidos. Outra forma de análise foi a sobreposição de imagens no CAD/CAM, com a finalidade de verificar se há semelhanças ou diferenças dimensionais entre o modelo piloto e as amostras. As medidas obtidas foram submetidas ao teste ANOVA com comparações múltiplas pelo teste de Tukey (α=0,05). Resultados: De acordo com as mensurações, a técnica que apresentou maior discordância do modelo piloto foi a T4, não havendo diferença entre as outras técnicas. Na avaliação em CAD/CAM, as técnicas T4 e T3 apresentaram maiores diferenças em relação ao modelo original de acordo com as imagens sobrepostas. Conclusões: Todas as técnicas estudadas apresentaram alterações dimensionais, em especial a técnica simultânea e a sem alívio, tanto nas medidas obtidas quanto na análise em CAD/CAM.

Objetives: To compare different impression techniques with addition silicone, by means of copy accuracy through manual measurements and overlaping in CAD/CAM. Material and methods: Four impressions of a same pilot model were carried out with silicone addition in different techniques: T1 ­ two steps with cut-back; T2 ­ two steps with PVC film relief; T3 ­ two steps without relief; and T4 ­ one step. The accuracy of the 4 different impression techniques was assessed by measuring 5 dimensions on stone casts poured from the impressions of the pilot model. Another analysis was carried out in CAD/CAM using the overlaping of the casts and the pilot model, in order to verify dimensional similarities and differences between them. The values obtained were submitted to ANOVA and Tukey test, for multiple comparisons (α=0.05). Results: According to the measures done, the technique that generated the greatest difference from the pilot model was T4, with no difference among the other techniques. In CAD/CAM analysis, techniques T4 and T3 presented more differences from the original model. Conclusions: All studied techniques presented dimensional changes, mainly the 1 step and the 2 step without relief, in both methods, measures and CAD/CAM analysis.

Primary stability of implants with peri-implant bone defects of various widths: an in vitro investigation

PURPOSE: This study aimed to evaluate the effects of i) the extent of peri-implant bone defects and ii) the application of bone cement on implant stability with respect to the measurement direction. METHODS: In 10 bovine rib bones, 4 implant osteotomies with peri-implant bone defects of various widths were prepared: i) no defect (D0), ii) a 2-mm-wide defect (D2), iii) a 4-mm-wide defect (D4), and iv) a 8-mm-wide defect (D8). The height of all defects was 10 mm. Implant stability quotient (ISQ) values and Periotest values (PTVs) were measured after implant placement and bone cement application. RESULTS: With increasing defect width, decreased ISQs and increased PTVs were observed. Statistically significant differences were found between groups D0 and D8, D0 and D4, and D2 and D8. Prior to bone cement application, inconsistent PTVs were found in group D8 depending on the measurement direction. Bone cement increased the implant stability. CONCLUSION: Peri-implant bone deficits measuring around 50% of the implant surface compromised implant stability. Clinically, PTVs should be cautiously interpreted in implants with large peri-implant defects due to inconsistent recordings with respect to the measurement direction.

Three-dimensional geometric model of the middle segment of the thoracic spine based on graphical images for finite element analysis

Abstract Introduction: Biomedical studies involve complex anatomical structures, which require specific methodology to generate their geometric models. The middle segment of the thoracic spine (T5-T10) is the site of the highest incidence of vertebral deformity in adolescents. Traditionally, its geometries are derived from computed tomography or magnetic resonance imaging data. However, this approach may restrict certain studies. The study aimed to generate two 3D geometric model of the T5-T10 thoracic spine segment, obtained from graphical images, and to create mesh for finite element studies. Methods A 3D geometric model of T5-T10 was generated using two anatomical images of T6 vertebra (side and top). The geometric model was created in Autodesk® Maya® 3D 2013, and the mesh process in HiperMesh and MeshMixer (v11.0.544 Autodesk). Results The T5-T10 thoracic segment model is presented with its passive components, bones, intervertebral discs and flavum, intertransverse and supraspinous ligaments, in different views, as well as the volumetric mesh. Conclusion The 3D geometric model generated from graphical images is suitable for application in non-patient-specific finite element model studies or, with restrictions, in the use of computed tomography or magnetic resonance imaging. This model may be useful for biomechanical studies related to the middle thoracic spine, the most vulnerable site for vertebral deformations.

Primary implant stability in a bone model simulating clinical situations for the posterior maxilla: an in vitro study

PURPOSE: The aim of this study was to determine the influence of anatomical conditions on primary stability in the models simulating posterior maxilla. METHODS: Polyurethane blocks were designed to simulate monocortical (M) and bicortical (B) conditions. Each condition had four subgroups measuring 3 mm (M3, B3), 5 mm (M5, B5), 8 mm (M8, B8), and 12 mm (M12, B12) in residual bone height (RBH). After implant placement, the implant stability quotient (ISQ), Periotest value (PTV), insertion torque (IT), and reverse torque (RT) were measured. Two-factor ANOVA (two cortical conditions×four RBHs) and additional analyses for simple main effects were performed. RESULTS: A significant interaction between cortical condition and RBH was demonstrated for all methods measuring stability with two-factor ANOVA. In the analyses for simple main effects, ISQ and PTV were statistically higher in the bicortical groups than the corresponding monocortical groups, respectively. In the monocortical group, ISQ and PTV showed a statistically significant rise with increasing RBH. Measurements of IT and RT showed a similar tendency, measuring highest in the M3 group, followed by the M8, the M5, and the M12 groups. In the bicortical group, all variables showed a similar tendency, with different degrees of rise and decline. The B8 group showed the highest values, followed by the B12, the B5, and the B3 groups. The highest coefficient was demonstrated between ISQ and PTV. CONCLUSIONS: Primary stability was enhanced by the presence of bicortex and increased RBH, which may be better demonstrated by ISQ and PTV than by IT and RT.

Virtual dissection table including the Visible Korean images, complemented by free software of the same data / Mesa de disección virtual que incluye las imágenes de Visible Korean, complementadas por programa de libre acceso con igual información

The objective of this study was to introduce the complementary relationship between virtual dissection table (simply, table) and free software, since authors tried to aid interested people in their studying digital human anatomy. Visible Korean (VK) team had presented the serially sectioned images and outlined images of a male cadaver. Thereafter, Anatomage (San Jose, CA) manufactured the table by making 3-dimensional (3D) volume models from the data. Separately, the VK team reconstructed surface models from the same data and inputted the models in portable document format (PDF) file, which can be opened on the personal computer. The software to browse the sectioned and outlined images was also programmed by VK team. In this report, the table and the VK free software were compared to establish their supplementary potentiality. Both the table and free software displayed equivalent 3D models reconstructed from the same sectioned images. In both platforms, the models were labeled for users to recognize the individual structures. Both the table and the free software had respective features to enhance the virtual dissecting experience. The table came with its designated hardware with life-sized display, whereas VK software could be run in any personal computer without burden. The coexistence of the table and free software will enrich the people learning anatomy. With increasing VK data and free software, more and more commercial or complimentary products are expected to be produced.

El objetivo de este estudio fue introducir la relación complementaria entre una mesa virtual de disección (simplemente, la mesa) y un programa de libre acceso. Mediante este proceso los autores trataron de ayudar a aquellas personas interesadas en el estudio de la anatomía humana digital. El equipo Visible Korean (VK) había presentado las imágenes de secciones consecutivas e imágenes de un cadáver de sexo masculino. Partiendo de ese punto, la compañía Anatomage fabricó la mesa produciendo con los datos modelos dimensionales de volumen (3D). En forma paralela, el equipo VK reconstruyó los modelos de superficie con los mismos datos y de entrada de los modelos en formato de documento portátil (PDF), que se pudieran abrir en el ordenador personal. El equipo VK además lo programó para navegar a través de las imágenes seccionadas y descritas. En este informe, la mesa y el programa VK fueron comparados para establecer su potencialidad complementaria. Tanto la mesa como el programa de libre acceso muestran modelos 3D equivalentes reconstruidos a partir de las mismas imágenes seccionadas. En ambas plataformas, se marcaron los modelos para que los usuarios reconozcan las estructuras individuales. Tanto la mesa y el programa libre tenían características respectivas para mejorar la experiencia de disección virtual. La mesa incluía el hardware designado con la pantalla de tamaño natural, mientras que el programa VK podía ser ejecutado en cualquier ordenador personal sin dificultad alguna. La coexistencia de la mesa y el programa libre pueden ser un apoyo importante para quienes estudien anatomía. Con el aumento de los datos de VK y el programa libre, se espera que exista una mayor cantidad de productos comerciales o gratuitos.

Mandibular intraosseous squamous cell carcinoma lesion associated with odontogenic keratocyst: a case report

Squamous cell carcinoma (SCC) is the most common malignant tumor in the oral cavity, and it accounts for about 90% of all oral cancers. Several risk factors for oral SCC have been identified; however, SCC associated with odontogenic keratocysts have rarely been reported. The present study describes the case of a 36-year-old man with SCC of the right ramus of the mandible, which was initially diagnosed as a benign odontogenic cyst. He underwent enucleation at another hospital followed by segmental mandibulectomy and fibular free flap reconstruction at our institution. In this case, we introduce a patient with oral cancer associated with odontogenic cyst on the mandible and report a satisfactory outcome with wide resection and immediate free flap reconstruction.

Three types of the serial segmented images suitable for surface reconstruction / 대한해부학회지

Stereoscopic surface models of human organs can be manipulated in real time. This is a significant feature of an interactive simulation system used for clinical practice. Objective surface models are obtainable from the accumulation of each structure's serial outlines, followed by surface reconstruction. The segmented images including the outlines can be divided into outlined images, white-filled images, and color-filled images. The purpose of this study was to report the benefits of the three types of segmented images for surface reconstruction. For the raw data, sectioned images of a male cadaver head were used. In the sectioned images, 91 structures were delineated for the preparation of 234 serial outlined images. The outlined images were converted into white-filled and color-filled images; the reverse conversion was also possible. The outlined images, including the original sectioned images, could be the source not only of surface models but also of volume models. The white-filled images, with a minimal file size, were preferred for separate surface reconstruction of the individual structures. The color-filled images, which allowed for recognition of the entire outlined structures simultaneously, were regarded as a good choice for the construction of several surface models. For the process, we employed a variety of software packages including those for animation, where the images were compatible. This information can be used by other investigators to build their own three-dimensional models. In addition, the surface models of detailed structures in the head, accompanied by the corresponding sectioned and segmented images, will hopefully contribute to various simulations that can be useful to clinicians.

Avaliação de um modelo anatômico sintético tridimensional de assoalho pélvico no ensino de anatomia comparado com a pélve cadavérica / A synthetic three-dimensional pelvic model as na effective didactic tool compared to cadaveric pelvis

Introdução e objetivos: O estudo da Anatomia humana se faz imprescindível para o conhecimento e compreensão do corpo humano como um todo, na importância e interação de todas as suas estruturas e características de cada um de seus órgãos ou partes, como meio essencial para promover a vida e cura dos males, intenção primária no ato de cuidar, enquanto técnica, arte e ciência, no seu mais expressivo compromisso (1). Além disto, a aula prática com o uso de componentes anatômicos manipuláveis é essencial para um bom processo de ensino e aprendizagem. Portanto, o componente pedagógico do material utilizado é essencial, de forma que as ferramentas escolhidas possam agregar valor na construção de uma aprendizagem significativa dos alunos. Os objetivos deste estudo foram avaliar: 1- o Modelo Anatômico Sintético de Assoalho Pélvico (MASAP) como uma ferramenta didática, comparando o mesmo com a pelve cadavérica (PC) durante a aula prática de Anatomia, e 2- a satisfação dos estudantes com ambos os métodos. Materiais e métodos: Foram utilizadas pelves cadavéricas e modelos anatômicos sintéticos de pelve. A pesquisa foi do tipo experimental, desenvolvida através de estudo prospectivo longitudinal. Sessenta e sete estudantes de Medicina, voluntários para este estudo, foram submetidos a um teste teórico preliminar (TTP) e a uma aula teórica de anatomia do assoalho pélvico. Após esta aula os estudantes foram randomizados em três grupos: G1, G2 e G3. G1 submeteu-se a aula prática tradicional de anatomia (APT) com o uso de PC, e G2 submeteu-se à aula prática proposta com uso do MASAP (APM). G3, denominado grupo controle, não foi submetido à aula prática. Um teste teórico final (TTF) foi aplicado para todos os grupos G1, G2 e G3. G1 e G2 foram submetidos a uma avaliação de satisfação relativa ao método utilizado para realização da aula prática (Avaliação do método - AM).

The study of human anatomy is indispensable for knowledge and understanding of the human body as a whole, that is to say, the importance and interaction of all its structures and characteristics of each of its organs or parts, as an essential means to promote life and healing ills, primary intention in the act of caring, while technical, art and science, in its most significant commitment (1). Furthermore, the practice class using a comprehensive and manageable anatomic component is fundamental for a good teaching and learning process. The goals of this study were to evaluate: 1- the synthetic anatomic model of pelvic floor (SAMPF) as a didactic tool comparing it to the traditional anatomic class using cadaveric pelvis (CP) and 2- the satisfaction of the students with both didactic methods. Sixty seven medicine students, volunteers for this study, received a conventional theoretic anatomy class. Following this class, all students were randomized in 3 groups (G1, G2 and G3). G1 and G2 attended anatomical classes with different didactic methods, respectively: traditional practice anatomy class (TPC), practice anatomy class with SAMPF (SPC).

Realistic Anatomical Prostate Models for Surgical Skills Workshops Using Ballistic Gelatin for Nerve-Sparing Radical Prostatectomy and Fruit for Simple Prostatectomy

PURPOSE: Understanding of prostate anatomy has evolved as techniques have been refined and improved for radical prostatectomy (RP), particularly regarding the importance of the neurovascular bundles for erectile function. The objectives of this study were to develop inexpensive and simple but anatomically accurate prostate models not involving human or animal elements to teach the terminology and practical aspects of nerve-sparing RP and simple prostatectomy (SP). MATERIALS AND METHODS: The RP model used a Foley catheter with ballistics gelatin in the balloon and mesh fabric (neurovascular bundles) and balloons (prostatic fascial layers) on either side for the practice of inter- and intrafascial techniques. The SP model required only a ripe clementine, for which the skin represented compressed normal prostate, the pulp represented benign tissue, and the pith mimicked fibrous adhesions. A modification with a balloon through the fruit center acted as a "urethra." RESULTS: Both models were easily created and successfully represented the principles of anatomical nerve-sparing RP and SP. Both models were tested in workshops by urologists and residents of differing levels with positive feedback. CONCLUSIONS: Low-fidelity models for prostate anatomy demonstration and surgical practice are feasible. They are inexpensive and simple to construct. Importantly, these models can be used for education on the practical aspects of nerve-sparing RP and SP. The models will require further validation as educational and competency tools, but as we move to an era in which human donors and animal experiments become less ethical and more difficult to complete, so too will low-fidelity models become more attractive.