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Id: biblio-974326
Autor: Fraga, Martín; Fernández, Sofía; Perelmuter, Karen; Pomiés, Nicolle; Cajarville, Cecilia; Zunino, Pablo.
Título: The use of Prevotella bryantii 3C5 for modulation of the ruminal environment in an ovine model
Fonte: Braz. j. microbiol;49(supl.1):101-106, 2018. tab, graf.
Idioma: en.
Projeto: Agencia Nacional de Investigación.
Resumo: Abstract In the Southern Hemisphere, ruminants are mostly raised in grazing systems where animals consume forage and are supplemented with low amounts of concentrates. Concentrates are usually given separately and are rapidly ingested. This practice leads to changing rumen environment conditions during the day, may alter the rumen microbial metabolism and could affect host performance. The native ruminal Prevotella bryantii strain 3C5 was administered every 48 h to wethers under experimental conditions simulating Southern-Hemisphere feeding to evaluate its potential as a rumen fermentation modulator. The inoculum potential was assessed on day 17. The ammonia nitrogen (NH3-N), volatile fatty acids and ruminal pH were monitored on a 24-h basis 19 days after the beginning of the experiment, and the microbial community structure was assessed by pyrosequencing. The administration of P. bryantii modified the fermentation products and daily pH values compared to the control. The NH3-N concentration in the rumen of treated animals was significantly higher than that of the untreated animals. Modification of the ruminal environment and fermentation pathways was achieved without altering the general structure of the microbial community or the potential methane production. P. bryantii 3C5 could be considered in potential probiotic formulations for ruminants in semi-intensive systems.
Descritores: Rúmen/microbiologia
Prevotella/metabolismo
-Rúmen/metabolismo
Rúmen/química
Ovinos
Prevotella/genética
Digestão
Ácidos Graxos Voláteis/metabolismo
Fermentação
Amônia/metabolismo
Concentração de Íons de Hidrogênio
Modelos Biológicos
Limites: Animais
Masculino
Responsável: BR1.1 - BIREME


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Id: lil-777093
Autor: Araujo, Walter Junior Boim; Timi, Jorge Rufino Ribas; Erzinger, Fabiano Luiz; Caron, Filipe Carlos; Cambrussi, Alan Knolseisen.
Título: Development of an ex vivo model of endovenous laser ablation of the great saphenous vein in a pilot study
Fonte: Acta cir. bras;31(3):161-167, Mar. 2016. graf.
Idioma: en.
Resumo: ABSTRACT PURPOSE: To develop an ex vivo model for the analysis of macroscopic, histological and immunohistochemical changes after experimental endovenous laser ablation (EVLA) of the great saphenous vein (GSV). METHODS: We describe a model produced with glass tubes and introducer sheaths to mimic the physiological conditions of EVLA procedures, such as tumescence and blood flow. A pilot study was conducted to evaluate an ex vivo procedure of EVLA of an incompetent GSV segment using a 1470-nm radial fiber diode laser (7 W power) and an automatic pull-back device. The vein segment was analyzed macroscopically and by hematoxylin & eosin staining, elastic fiber histochemistry, Gomori's trichrome staining, and alpha-smooth muscle actin immunohistochemistry. RESULTS: No perforations were observed macroscopically. No muscle cell adhesion was observed in the central part of the ablated vein, showing tissue disruption. There was low labeling for elastic fibers, disruption of muscle fibers, and a reduced expression of the specific marker for this cell type. CONCLUSION: This ex vivo endovenous laser ablation model is a low cost alternative to in vivo experiments, providing standardized experimental conditions.
Descritores: Veia Safena/cirurgia
Terapia a Laser/métodos
Lasers Semicondutores/uso terapêutico
Músculo Liso Vascular/metabolismo
-Veia Safena/metabolismo
Veia Safena/patologia
Varizes/cirurgia
Varizes/metabolismo
Varizes/patologia
Projetos Piloto
Reprodutibilidade dos Testes
Resultado do Tratamento
Modelos Biológicos
Limites: Seres Humanos
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


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Id: lil-520790
Autor: Mejia, J; Galvis-Alonso, O. Y; Braga, J; Corrêa, R; Leite, J. P; Simões, M. V.
Título: Methodological approaches to planar and volumetric scintigraphic imaging of small volume targets with high spatial resolution and sensitivity
Fonte: Braz. j. med. biol. res = Rev. bras. pesqui. méd. biol;42(8):692-699, Aug. 2009. ilus.
Idioma: en.
Projeto: FAPESP; . FAPESP CInAPCe.
Resumo: Single-photon emission computed tomography (SPECT) is a non-invasive imaging technique, which provides information reporting the functional states of tissues. SPECT imaging has been used as a diagnostic tool in several human disorders and can be used in animal models of diseases for physiopathological, genomic and drug discovery studies. However, most of the experimental models used in research involve rodents, which are at least one order of magnitude smaller in linear dimensions than man. Consequently, images of targets obtained with conventional gamma-cameras and collimators have poor spatial resolution and statistical quality. We review the methodological approaches developed in recent years in order to obtain images of small targets with good spatial resolution and sensitivity. Multipinhole, coded mask- and slit-based collimators are presented as alternative approaches to improve image quality. In combination with appropriate decoding algorithms, these collimators permit a significant reduction of the time needed to register the projections used to make 3-D representations of the volumetric distribution of target's radiotracers. Simultaneously, they can be used to minimize artifacts and blurring arising when single pinhole collimators are used. Representation images are presented, which illustrate the use of these collimators. We also comment on the use of coded masks to attain tomographic resolution with a single projection, as discussed by some investigators since their introduction to obtain near-field images. We conclude this review by showing that the use of appropriate hardware and software tools adapted to conventional gamma-cameras can be of great help in obtaining relevant functional information in experiments using small animals.
Descritores: Projeto Auxiliado por Computador
Imagem Tridimensional/veterinária
Modelos Biológicos
Tomografia Computadorizada de Emissão de Fóton Único/veterinária
-Aumento da Imagem
Imagem Tridimensional/métodos
Reprodutibilidade dos Testes
Sensibilidade e Especificidade
Tomografia Computadorizada de Emissão de Fóton Único/métodos
Limites: Animais
Tipo de Publ: Research Support, Non-U.S. Gov't
Revisão
Responsável: BR1.1 - BIREME


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Id: biblio-1002267
Autor: Grossi, Bruno; Loncomilla, Patricio; Canals, Mauricio; Ruiz-Del-Solar, Javier.
Título: Are cursorial birds good kinematic models of non-avian theropods? / ¿Son los pájaros corredores buenos modelos cinemáticos de terópodos no aviares?
Fonte: Int. j. morphol;37(2):620-625, June 2019. tab, graf.
Idioma: en.
Projeto: FONDECYT; . FONDECYT.
Resumo: Determining kinematics of hindlimbs of theropod dinosaurs has been a challenge. Since cursorial birds are phylogenetically closest to theropod dinosaurs they are commonly used as a kinematic model of theropod dinosaur locomotion. Using a comparative biomechanical approach, we found that cursorial birds have a different morphology of legs than non avian theropodos and that appears to be that felines and ungulates share more morphological properties in the hindlimbs with theropod dinosaurs than cursorial birds. We calculated the ratio between the lower leg and the femur, and the relative length of the tibia and the metatarsus with respect to the length of the femur in cursorial birds, as well as felines, ungulates and non-avian theropods. We found that as the length of the femur increases, the length of the lower leg increases similarly in felines, ungulates and non-avian theropods. On the other hand, existing and extinct cursorial birds did not follow this pattern. This observation suggests that the hindlimb of cursorial birds are not well suited to serve as kinematic models for hindlimb of extinct theropod dinosaur locomotion.

Determinar la cinemática de los miembros pelvianos de los dinosaurios terópodos ha sido un desafío. Dado que las aves corredoras son filogenéticamente más cercanas a los dinosaurios terópodos, son comúnmente utilizadas como modelo cinemático de la locomoción del dinosaurio terópodo. Usando un enfoque biomecánico comparativo, encontramos que las aves corredoras tienen una morfología de pies diferente a la de los terópodos no aviares y parece ser que los felinos y los ungulados comparten más propiedades morfológicas en los pies con los dinosaurios terópodos que las aves corredoras. Calculamos la proporción entre la parte inferior de la pierna y el fémur, y la longitud relativa de la tibia y el metatarso con respecto a la longitud del fémur en aves corredoras, así como en los terópodos no aviares y ungulados. Encontramos que a medida que aumenta la longitud del fémur, la longitud de la parte inferior de la pierna aumenta de manera similar en los terópodos, los ungulados y los terópodos no aviares. Por otro lado, las aves corredoras existentes y extintas no siguieron este patrón. Esta observación sugiere que el miembro pelviano de las aves corredoras no es adecuada para servir como modelos cinemáticos de locomoción del miembro pelviano del dinosaurio terópodo extinto.
Descritores: Fenômenos Biomecânicos/fisiologia
Aves/fisiologia
Dinossauros/fisiologia
Membro Posterior/fisiologia
Locomoção/fisiologia
-Postura
Aves/anatomia & histologia
Caminhada/fisiologia
Dinossauros/anatomia & histologia
Membro Posterior/anatomia & histologia
Modelos Biológicos
Limites: Animais
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-893082
Autor: Gayol-Mérida, Diana Alicia; Enríquez-Rivera, Luis Alberto; Araujo-Monsalvo, Víctor Manuel; Alemán-Pérez, Aylenid; Baez-Rivas, Livier; Domínguez-Hernández, Víctor Manuel.
Título: Analysis of behavior of forces in a pelvis-soft tissue mechanical model / Análisis del comportamiento de fuerzas en un modelo mecánico de pelvis-tejido blando
Fonte: Int. j. morphol;35(3):979-985, Sept. 2017. ilus.
Idioma: en.
Projeto: Consejo Nacional de Ciencia y Tecnología.
Resumo: Pressure ulcers are tissue damage resulting from the constant pressure on the underlying soft tissue to bony prominences for long periods. Some of the most common ulcers are developed at the ischial tuberosities area (ITs). It has been found that stresses produced in the underlying tissue to the ITs may exceed 5 to 11 times the surface stresses, making it necessary to estimate the forces generated between the soft tissue and the ITs. However, it is not possible to determine these stresses in vivo in a patient, due to ethical reasons. This paper presents a mechanical model of the pelvis-soft tissue in order to study the behavior of contact forces. The model simulates the load on the ITs of a male subject of 70 kg weight and 1.70 m height, which were recorded for 8 min. The registered forces in the model were compared with the surface forces estimated from pressure records measured by the Force Sensing Array system in a patient with spinal cord injury. After 2 min, both forces measured in the model, and the ones estimated in the patient followed the trend described by Crawford during clinical measurements of pressures during sitting. It was also found in the model that measured forces below the ITs are higher than those measured below soft tissue, which suggests that the model may be valid for the study of the forces generated inside the tissue.

Las úlceras por presión son daños en el tejido, derivados de la presión constante por periodos prolongados sobre el tejido blando subyacente a una prominencia ósea, algunas de las úlceras más comunes se desarrollan en la zona de las tuberosidades isquiáticas (TI´s). Se ha detectado que esfuerzos generados en el tejido subyacente a las TI´s pueden exceder entre 5 a 11 veces a los esfuerzos superficiales, lo que hace necesario conocer las fuerzas que se generan entre el tejido blando y las TI´s, sin embargo medir estos esfuerzos in vivo en un sujeto, no es posible por razones éticas. Este trabajo presenta un modelo mecánico del sistema pelvis-tejido blando con la finalidad de estudiar el comportamiento de las fuerzas, el modelo simula la carga en las TI´s de un sujeto masculino de 70 kg y 1,70 m, en el cual se registraron por 8 min. Las fuerzas registradas en modelo fueron comparadas con las fuerzas superficiales estimadas a partir de los registros de presión medidas por el sistema Force Sensing Array, en un paciente con lesión medular. A partir de 2 min, tanto fuerzas medidas en el modelo, como estimadas en el paciente, siguen la tendencia descrita por Crawford para mediciones de presiones clínicas durante la sedestación, también se encontró en el modelo que las fuerzas medidas por debajo de las TI's son mayores a las medidas debajo del tejido blando; lo que sugiere que el modelo puede ser válido, para el estudio de las fuerzas que se generan al interior del tejido.
Descritores: Estresse Mecânico
Lesão por Pressão
Modelos Biológicos
Limites: Seres Humanos
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-839141
Autor: Teixeira, Ligia; Basso, Fernanda Gonçalves; Hebling, Josimeri; Costa, Carlos Alberto de Souza; Mori, Graziela Garrido; Silva-Sousa, Yara Teresinha Corrêa; Oliveira, Camila Fávero de.
Título: Cytotoxicity Evaluation of Root Canal Sealers Using an In Vitro Experimental Model with Roots
Fonte: Braz. dent. j;28(2):165-171, mar.-Apr. 2017. tab, graf.
Idioma: en.
Projeto: (CAPES.
Resumo: Abstract The aim of the present study was to evaluate the cytotoxicity of root canal sealers under conditions closely resembling a clinical reality. A primary human fibroblast cell line was seeded in 24-well acrylic plates with Dulbecco’s modified Eagle’s medium supplemented with 10% serum fetal bovine (SFB) and incubated for 24 h. Root canals from premolars were filled and individually attached to nylon devices to be stabilized in the wells with the already seeded cells. Specimens were divided into groups as follows: Control: gutta-percha cones (GPC); AH Plus+GPC; Sealapex+GPC; MTA Fillapex+GPC and Endofill+GPC. After 24 and 48 h, cell viability and morphology were evaluated by MTT assay and scanning electron microscopy (SEM), respectively. Statistical analysis was performed by Mann-Whitney test, complemented by Kruskal Wallis test (p<0.05). Only Endofill presented cytotoxicity after 24 h. MTA Fillapex and Endofill reduced the production of succinic desidrogenase after 48 h. AH Plus was non-toxic at any time point. SEM showed that the AH Plus and MTA Fillapex groups presented fibroblasts with morphology close to the control group, while the Endofill group presented few cells with thin extensions cells. The present study showed that good results were present in AH Plus and Sealapex, but not the Endofill group after 48 h. The method used enabled evaluation of the cytotoxicity of the studied sealers that diffused through the root apex.

Resumo O objetivo do presente estudo foi avaliar a citotoxicidade dos cimentos dos canais radiculares em condições próximas à realidade clinica. Uma linhagem primária de fibrolastos humanos foi semeada em placas acrílicas de 24-poços com meio de cultura Dulbecco’s modified Eagle’s medium suplementado com 10% de soro fetal bovino e incubados por 24 h. Os canais radiculares de pré-molares foram obturados e individualmente adaptados aos dispositivos de nylon para serem estabilizados nos poços com as células já semeadas. Amostras foram dividas de acordo com os grupos: Controle: cones de gutta-percha (CGP); AH Plus+CGP; Sealapex+CGP; MTA Fillapex+CGP e Endofill+CGP. Após 24 e 48 h, a viabilidade e a morfologia celular foram avaliadas pelo ensaio de MTT e microscopia eletrônica de varredura (MEV), respectivamente. Análises estatísticas foram realizadas pelo teste de Mann-Whitney, complementadas por Kruskal Wallis (p<0,05). Apenas o Endofill apresentou citotoxicidade após 24 h. MTA Fillapex e Endofill reduziram a produção da enzima desidrogenase succinica após 48 h. AH Plus não apresentou toxicidade em nenhum momento. MEV mostrou que os grupos AH Plus e o MTA Fillapex apresentaram fibroblastos com morfologia próxima ao grupo controle, enquanto que o grupo do Endofill apresentou poucas células com finos prolongamentos. O presente estudo demonstrou que resultados satisfatórios foram apresentados nos grupos AH Plus e Sealapex, mas não para o Endofill após 48 h. O método utilizado permitiu avaliar a citotoxicidade dos cimentos que se difundem pelo ápice radicular.
Descritores: Materiais Restauradores do Canal Radicular/toxicidade
Raiz Dentária/efeitos dos fármacos
Modelos Biológicos
-Técnicas In Vitro
Microscopia Eletrônica de Varredura
Linhagem Celular
Meios de Cultura
Limites: Seres Humanos
Responsável: BR1.1 - BIREME


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Id: biblio-841791
Autor: Zambenedetti, Miriam Ribas; Pavoni, Daniela Parada; Dallabona, Andreia Cristine; Dominguez, Alejandro Correa; Poersch, Celina de Oliveira; Fragoso, Stenio Perdigão; Krieger, Marco Aurélio.
Título: Internal control for real-time polymerase chain reaction based on MS2 bacteriophage for RNA viruses diagnostics
Fonte: Mem. Inst. Oswaldo Cruz;112(5):339-347, May 2017. tab, graf.
Idioma: en.
Resumo: BACKGROUND Real-time reverse transcription polymerase chain reaction (RT-PCR) is routinely used to detect viral infections. In Brazil, it is mandatory the use of nucleic acid tests to detect hepatitis C virus (HCV), hepatitis B virus and human immunodeficiency virus in blood banks because of the immunological window. The use of an internal control (IC) is necessary to differentiate the true negative results from those consequent from a failure in some step of the nucleic acid test. OBJECTIVES The aim of this study was the construction of virus-modified particles, based on MS2 bacteriophage, to be used as IC for the diagnosis of RNA viruses. METHODS The MS2 genome was cloned into the pET47b(+) plasmid, generating pET47b(+)-MS2. MS2-like particles were produced through the synthesis of MS2 RNA genome by T7 RNA polymerase. These particles were used as non-competitive IC in assays for RNA virus diagnostics. In addition, a competitive control for HCV diagnosis was developed by cloning a mutated HCV sequence into the MS2 replicase gene of pET47b(+)-MS2, which produces a non-propagating MS2 particle. The utility of MS2-like particles as IC was evaluated in a one-step format multiplex real-time RT-PCR for HCV detection. FINDINGS We demonstrated that both competitive and non-competitive IC could be successfully used to monitor the HCV amplification performance, including the extraction, reverse transcription, amplification and detection steps, without compromising the detection of samples with low target concentrations. In conclusion, MS2-like particles generated by this strategy proved to be useful IC for RNA virus diagnosis, with advantage that they are produced by a low cost protocol. An attractive feature of this system is that it allows the construction of a multicontrol by the insertion of sequences from more than one pathogen, increasing its applicability for diagnosing different RNA viruses.
Descritores: Vírus de RNA/genética
Hepatite C/diagnóstico
Hepacivirus/genética
Escherichia coli/genética
Reação em Cadeia da Polimerase em Tempo Real/métodos
-Levivirus/genética
Modelos Biológicos
Responsável: BR1.1 - BIREME


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Id: lil-780559
Autor: Loyola-González, Pablo Octavio; Torassa, Daniel; Dominguez, Alejandro.
Título: Estudio comparativo sobre el comportamiento y la distribución de las tensiones en implantes dentales cortos e implantes dentales estándares en la región posterior del maxilar superior: Un estudio en elementos finitos / Comparative study on the behaviour and tension distribution in short and standard dental implants in the back of the upper jaw
Fonte: Rev. clín. periodoncia implantol. rehabil. oral (Impr.);9(1):36-41, abr. 2016. ilus, tab.
Idioma: es.
Resumo: Objetivos Estudios concluyen que la máxima tensión y distribución de fuerzas se produciría alrededor del cuello del implante. Comparar la distribución de las tensiones entre un implante dental corto oseointegrado en distintas disponibilidades óseas verticales y un implante estándar oseointegrado en el sector posterior del maxilar en un terreno mixto formado por hueso propio del paciente y Bio-Oss®. Conocer la distribución de las tensiones. Estudiar el aumento del diámetro del implante corto. Analizar si los resultados avalan el uso de implantes cortos. Material y método El método de elementos finitos (MEF), que permite resolver ecuaciones diferenciales asociadas a un problema físico sobre geometrías complicadas. En este trabajo la región geométrica es un modelo tridimensional de un implante, su corona, y una porción de la región ósea de la zona estudiada. Los modelos fueron sometidos a fuerzas de oclusión de 150 N en ángulo de 30° Norma ISO 14801:2003. El software de MEF que se utiliza es el ABAQUS de la empresa Dassault Systèmes. Resultados Máximos valores se concentran en la porción cervical del implante. Las tensiones en el implante están dentro del mismo rango. A mayor módulo de elasticidad de los elementos que componen los modelos, mayor es la absorción de las fuerzas. Las tensiones en el hueso cortical no mostraron diferencias, pero en el modelo que aumentamos el diámetro del implante a 4,8 se produce una marcada disminución de las tensiones. La comparativa de las tensiones en el hueso esponjoso muestra que existe diferencia en las tensiones producidas en el hueso con Bio-Oss® y está localizado en la porción apical del implante quedando lejos de la zona de mayor concentración de los esfuerzos. Conclusiones La máxima concentración de las fuerzas a nivel cervical es independiente de la longitud del implante, siendo más favorable el aumento del diámetro. El uso de implantes cortos en hueso de baja calidad parece posible.

Objectives Current studies conclude that the maximum tension and the greater distribution of forces should occur around the implant neck. To compare the distribution of stress between a short dental implant osseointegrated in different available vertical bones and standard osseointegrated implants in the posterior maxilla in mixed terrain formed by the bone of the patient and Bio-Oss®. To determine the stress distribution. To study the increased diameter of the short implant. To determine whether the results support the use of short implants. Materials and methods The finite elements method (FEM), which helps to solve differential equations associated with a physical problem with complicated geometries, was used in this work, where the geometric region is a three-dimensional model of an implant, its crown, and a portion of the bone region of the studied area. The models were subjected to occlusion forces, 150 N Angle 30° ISO 14801: 2003. The MEF software used was called Abaqus from Dasssault Systemes Enterprise. Results The maximum values were concentrated in the cervical portion of the implant. Tensions in the implant are in the same range. The greater the elasticity of the elements contained in the module, the greater is the absorption of stress forces. The tension in the cortical bone showed no differences, but in the model where the diameter of the implant is increased to 4.8, a marked decrease occurs in the bone stress. The comparison of the stresses in the cancellous bone showed a difference in the stresses produced in the bone with Bio-Oss®, and it is located in the apical portion of the implant away from the area of the major stress concentration. Conclusions The maximum concentration of forces in cervical portion is independent of the length of the implant, being favourable to increase the diameter. It is possible to use low quality bone in for shorts implants.
Descritores: Implantes Dentários
Análise de Elementos Finitos
Análise do Estresse Dentário
-Estudo Comparativo
Modelos Biológicos
Limites: Seres Humanos
Responsável: CL58.1 - Biblioteca


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Id: lil-711562
Autor: Andrade, Valdir Cabral; Luthi, Leonardo Flores; Sato, Fabio Loureiro; Nascimento, Federico Felipe; Olate, Sergio; Albergaria-Barbosa, Jose Ricardo.
Título: Osteotomía sagital de rama mandibular con osteosíntesis en L invertido: estudio mecánico con fotoelasticidad / Sagittal split ramus osteotomy with L inverted osteosynthesis: A mechanical study with photoelasticity
Fonte: Int. j. odontostomatol. (Print);8(1):161-165, Apr. 2014. ilus.
Idioma: es.
Resumo: El objetivo de esta investigación es identificar las tensiones presentes en tornillos de osteosíntesis utilizados en la fijación de la osteotomía sagital de rama mandibular (OSRM). Se utilizaron dos modelos de OSRM realizados con resina fotoelástica donde el grupo 1 presentaba una osteotomía basilar recta mientras que el grupo 2 presentaba una osteotomía basilar angulada; en ambos se utilizo el sistema de L invertido para la osteosíntesis con tornillos 2.0 de 13 mm de longitud. Posteriormente el sistema fue instalado en un pilar sobre la maquina Instrom, donde se aplico una carga vertical de 1 mm/minuto hasta conseguir el desplazamiento de 3 mm; el punto de carga estuvo en la fosa central del primer molar. La distribución de franjas mostro mayor tensión en el tornillo mas próximo de la osteotomía en ambos grupos; en el grupo 2 se produjo una diseminación de fuerzas levemente hacia la basilar y en el grupo 1 se mantuvo la diseminación a través de la línea oblicua. Se puede concluir que ambas osteotomías mandibulares son eficientes en la distribución de cargas y que no se observan diferencias cualitativas entre tornillos en términos de cantidad de diseminación de energía

The aim of this research was to analyzed the tension in osteosynthesis screw used for fixation of sagittal split ramus osteotomy (SSRS). Was used two model of SSRS made in photoelastic resin; in one of them was include a basilar osteotomy and the another one only SSRS without basilar osteotomy; for both system was used inverted L osteosynthesis with 13 mm screw of 2.0 system. Posteriorly, the hemimandible was installed in Instrom machine with a vertical load of 1 mm/min until the displacement of 3 mm; the load point was on first molar. The fringe distribution show more tension in the screw close to osteotomy in both groups; when SSRS was united to basilar osteotomy was produced a inferior distribution of force and in the SSRS without basilar osteotomy group was maintained a distribution into the oblique line. It's was conclude that both mandibular osteotomies was efficient in load distribution and was not observed important differences between screw related to distribution of load
Descritores: Parafusos Ósseos
Análise do Estresse Dentário/métodos
Osteotomia Sagital do Ramo Mandibular/métodos
-Estresse Mecânico
Teste de Materiais
Fixadores Internos
Elasticidade
Modelos Biológicos
Limites: Seres Humanos
Responsável: CL1.1 - Biblioteca Central


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Id: lil-740949
Autor: Cisneros Hidalgo, Yosbel Ángel; González Carbonell, Raide Alfonso; Camue Corona, Ernesto; Oropesa Rodríguez, Yuri; Puentes Álvarez, Antonio.
Título: Aplicación de los modelos mecanobiológicos en los procesos de regeneración ósea / Application of mechano-biological models in bone regeneration process / Mise en application des modèles biomécaniques dans les processus de régénération osseuse
Fonte: Rev. cuba. ortop. traumatol;28(2):214-222, jul.-dic. 2014. ilus.
Idioma: es.
Resumo: Los modelos computacionales constituyen una herramienta necesaria en las investigaciones científicas. En este trabajo se muestra la utilización de las nuevas tecnologías, a través del Método de los Elementos Finitos en la implementación de los modelos mecanobiológicos usados en ortopedia. Se exponen los principales modelos mecano-reguladores que aparecen en la bibliografía y se ejemplifican las ventajas que proporcionan las técnicas de modelación en el pronóstico de la formación de nuevo tejido óseo, como respuesta biológica del organismo debido a la aplicación de cargas externas.

Computational models are a necessary tool in scientific researches. This paper deals with the use of new technologies, by using the Finite Element Method for the implementation of mechano-biological models used in orthopedic. Also the main mechano-regulator models are shown in this article, which are described in literature. On the other hand, the advantages provided by the modeling techniques during the prognosis of the new tissue formation, as a response of the organism to the application of external loads are stated by these authors.

Les modèles informatisées constituent un outil nécessaire dans les recherches scientifiques. Dans ce travail, on montre l’usage des nouvelles technologies, telle que la méthode des Éléments finis, dans la mise en application des modèles biomécaniques utilisés en orthopédie. On fait une révision des modèles mécano-régulateurs principaux apparus dans la littérature, et on met des exemples des bénéfices obtenus par les techniques de modélisation dans le pronostic de formation du nouveau tissu osseux comme réponse biologique du corps aux charges externes.
Descritores: Regeneração Óssea/fisiologia
Metodologias Computacionais
Manipulação Ortopédica/métodos
Modelos Biológicos
Limites: Seres Humanos
Responsável: CU1.1 - Biblioteca Médica Nacional



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