Avaliação biomecânica da mandibulotomia
Autor(a) principal: | |
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Data de Publicação: | 2011 |
Tipo de documento: | Tese |
Idioma: | por |
Título da fonte: | Repositório Institucional da UFU |
Texto Completo: | https://repositorio.ufu.br/handle/123456789/14701 |
Resumo: | Currently, cancer is still the cause of high death rates worldwide. Therefore, researchers are engaged in prevention and early diagnosis of this malignant disease that affects millions of people. Specifically in Brazil, it is recognized as a public health problem. Despide all efforts, the incidence of oral cancer in particular, is most often diagnosed in advanced stages. The mandibulotomy technique is used for surgical access of some tumors in this region.The surgical access to the tumors can be done using miniplates with titanium screws or steel wires systems. They are used to fixate the osteotomies and provide maximum stability for an appropriate osteosynthesis. However, there are many doubts regarding the best mounting configurations and biomechanical behavior related to the mandibulotomy technique. In this work, the technique using the fixation by miniplates and screws were evaluated in two ways: numerically, by means of the finite element method, and experimentally, for both midline and paramidline cut. Statistical analysis with Scott Knott method (p = 5%) was used to evaluate the experimental stability. The experimental data were used to validate the numerical models and, in sequence, the prediction equations for stability were obtained using similitude methods. The variables were optimized using genetic algorithms to allow indicate the best models that guarantee the best stability. The settings of mini plates and screws of these optimized models were applied to numerical models of a human jaw and compared with those conventional conditions used by surgeons in terms of stress and displacement levels. Considering midline mandibulotomy and measurements of relative displacement between osteotomy sides, the CM2M4I - P1P3 model (fixed with four screws and positioned internally to the osteotomy line with two miniplates placed, one in the lower and the other one little higher, a middle region of the mandible) showed better stability when compared to the conventional surgical one. The better stability condition of paramidline osteotomy was the CP2M4I - P2P3 model (fixed with four screws positioned internally in relation to the osteotomy line, with two miniplates located in the middle region of the mandible). In parallel, the union stability of the midline and paramidline osteotomies was also evaluated using fasteners with stainless steel wire. Actually, this stainless steel wire technique is in disuse and showed lower stability when compared to the miniplates and screws technique. It s conclude that some configurations of miniplate and screws can replace the conventional models currently used by surgeons. |
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Avaliação biomecânica da mandibulotomiaBiomechanical Evaluation of the Mandibulotomy TechniqueCâncerMandibulotomiaElementos finitosOtimizaçãoMiniplacasSimilitudeBiomecânicaMétodo dos elementos finitosBoca - CâncerMandibulotomyFinite elementOptimizationMiniplatesCNPQ::ENGENHARIAS::ENGENHARIA MECANICACurrently, cancer is still the cause of high death rates worldwide. Therefore, researchers are engaged in prevention and early diagnosis of this malignant disease that affects millions of people. Specifically in Brazil, it is recognized as a public health problem. Despide all efforts, the incidence of oral cancer in particular, is most often diagnosed in advanced stages. The mandibulotomy technique is used for surgical access of some tumors in this region.The surgical access to the tumors can be done using miniplates with titanium screws or steel wires systems. They are used to fixate the osteotomies and provide maximum stability for an appropriate osteosynthesis. However, there are many doubts regarding the best mounting configurations and biomechanical behavior related to the mandibulotomy technique. In this work, the technique using the fixation by miniplates and screws were evaluated in two ways: numerically, by means of the finite element method, and experimentally, for both midline and paramidline cut. Statistical analysis with Scott Knott method (p = 5%) was used to evaluate the experimental stability. The experimental data were used to validate the numerical models and, in sequence, the prediction equations for stability were obtained using similitude methods. The variables were optimized using genetic algorithms to allow indicate the best models that guarantee the best stability. The settings of mini plates and screws of these optimized models were applied to numerical models of a human jaw and compared with those conventional conditions used by surgeons in terms of stress and displacement levels. Considering midline mandibulotomy and measurements of relative displacement between osteotomy sides, the CM2M4I - P1P3 model (fixed with four screws and positioned internally to the osteotomy line with two miniplates placed, one in the lower and the other one little higher, a middle region of the mandible) showed better stability when compared to the conventional surgical one. The better stability condition of paramidline osteotomy was the CP2M4I - P2P3 model (fixed with four screws positioned internally in relation to the osteotomy line, with two miniplates located in the middle region of the mandible). In parallel, the union stability of the midline and paramidline osteotomies was also evaluated using fasteners with stainless steel wire. Actually, this stainless steel wire technique is in disuse and showed lower stability when compared to the miniplates and screws technique. It s conclude that some configurations of miniplate and screws can replace the conventional models currently used by surgeons.Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorDoutor em Engenharia MecânicaAtualmente o câncer ainda é a causa de inúmeras mortes no mundo, e por isso pesquisadores se dedicam à prevenção e diagnóstico precoce em torno dessa doença que afeta milhões de pessoas, sendo reconhecido no Brasil como um problema de saúde pública. Apesar dos esforços o câncer de boca, em especial, na maioria das vezes é diagnosticado em fase avançada da doença. Vários tipos de tratamentos são usados para o câncer de boca e orofaringe, dependendo da sua localização e estágio. A mandibulotomia é usada para o acesso cirúrgico para alguns tumores dessa região. Os meios mais utilizados para fixar os segmentos ósseos decorrentes deste procedimento são miniplacas e parafusos de titânio ou fios de aço, de maneira a garantir a máxima estabilidade da união para, assim, ocorrer de forma adequada a osteossíntese. Ainda existem muitas dúvidas com relação às melhores configurações de fixação e o comportamento biomecânico relacionado à técnica de mandibulotomia. Neste trabalho, a técnica da mandibulotomia, utilizando a fixação por miniplacas e parafusos de titânio, foi avaliada de duas maneiras: numérica, por meio do Método dos Elementos Finitos, e experimentalmente, tanto para corte mediano quanto para corte paramediano. A análise estatística, utilizando o método de Scott Knott (p=5%), avaliou as melhores condições de estabilidade feitas experimentalmente. Os resultados experimentais foram utilizados para validar alguns modelos numéricos, dos quais foram determinadas equações preditivas para o nível de estabilidade, utilizando a técnica da similitude. As variáveis de influência foram otimizadas utilizando algoritmos genéticos, permitindo indicar os melhores modelos que garantissem a melhor estabilidade. As configurações de miniplaca e parafusos destes modelos otimizados foram aplicadas em modelos numéricos de uma mandíbula humana e comparados com aquelas condições convencionais utilizadas pelos cirurgiões em termos de gradientes de tensões e deslocamentos relativos das partes osteotomizadas. Considerando o corte mediano e os níveis de deslocamento relativo entre os segmentos, verifica-se que o modelo CM2M4I P1P3 (fixado com quatro parafusos posicionados internamente em relação à linha de corte com duas miniplacas posicionadas, uma na região inferior e a outra um pouco mais acima, numa região média da mandíbula) apresentou melhor estabilidade quando comparado à solução convencional adotada pelos cirurgiões. Para o corte paramediano, a condição de melhor estabilidade foi para o modelo CP2M4I-P2P3 (fixado com quatro parafusos posicionados internamente em relação ao corte, com duas miniplacas posicionadas na região média da mandíbula). Paralelamente, a estabilidade da união de cortes mediano e paramediano também foi avaliada utilizando fixações com fios de aço inoxidável. Este tipo de fixação, em desuso nos dias atuais, apresentou estabilidade inferior às fixações feitas com miniplacas e parafusos de titânio. Por meio do estudo, concluiu-se que existem outras configurações de parafusos e miniplacas que podem substituir aquelas convencionalmente utilizadas pelos cirurgiões.Universidade Federal de UberlândiaBRPrograma de Pós-graduação em Engenharia MecânicaEngenhariasUFUSilva, Sindeval José dahttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4777762U4Araújo, Cleudmar Amaral dehttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4782336A0Rade, Domingos Alveshttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4781681T7Oliveira, Sônia Aparecida Goulart dehttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4785944D1Shimano, Marcos Massaohttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4745540J5Silva, Sidney Nicodemos dahttp://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4763737Y8Caixeta, Delma Pereira2016-06-22T18:39:30Z2011-10-032016-06-22T18:39:30Z2011-04-04info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisapplication/pdfapplication/pdfapplication/pdfapplication/pdfCAIXETA, Delma Pereira. Biomechanical Evaluation of the Mandibulotomy Technique. 2011. 332 f. Tese (Doutorado em Engenharias) - Universidade Federal de Uberlândia, Uberlândia, 2011.https://repositorio.ufu.br/handle/123456789/14701porinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFUinstname:Universidade Federal de Uberlândia (UFU)instacron:UFU2016-06-23T06:55:51Zoai:repositorio.ufu.br:123456789/14701Repositório InstitucionalONGhttp://repositorio.ufu.br/oai/requestdiinf@dirbi.ufu.bropendoar:2016-06-23T06:55:51Repositório Institucional da UFU - Universidade Federal de Uberlândia (UFU)false |
dc.title.none.fl_str_mv |
Avaliação biomecânica da mandibulotomia Biomechanical Evaluation of the Mandibulotomy Technique |
title |
Avaliação biomecânica da mandibulotomia |
spellingShingle |
Avaliação biomecânica da mandibulotomia Caixeta, Delma Pereira Câncer Mandibulotomia Elementos finitos Otimização Miniplacas Similitude Biomecânica Método dos elementos finitos Boca - Câncer Mandibulotomy Finite element Optimization Miniplates CNPQ::ENGENHARIAS::ENGENHARIA MECANICA |
title_short |
Avaliação biomecânica da mandibulotomia |
title_full |
Avaliação biomecânica da mandibulotomia |
title_fullStr |
Avaliação biomecânica da mandibulotomia |
title_full_unstemmed |
Avaliação biomecânica da mandibulotomia |
title_sort |
Avaliação biomecânica da mandibulotomia |
author |
Caixeta, Delma Pereira |
author_facet |
Caixeta, Delma Pereira |
author_role |
author |
dc.contributor.none.fl_str_mv |
Silva, Sindeval José da http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4777762U4 Araújo, Cleudmar Amaral de http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4782336A0 Rade, Domingos Alves http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4781681T7 Oliveira, Sônia Aparecida Goulart de http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4785944D1 Shimano, Marcos Massao http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4745540J5 Silva, Sidney Nicodemos da http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4763737Y8 |
dc.contributor.author.fl_str_mv |
Caixeta, Delma Pereira |
dc.subject.por.fl_str_mv |
Câncer Mandibulotomia Elementos finitos Otimização Miniplacas Similitude Biomecânica Método dos elementos finitos Boca - Câncer Mandibulotomy Finite element Optimization Miniplates CNPQ::ENGENHARIAS::ENGENHARIA MECANICA |
topic |
Câncer Mandibulotomia Elementos finitos Otimização Miniplacas Similitude Biomecânica Método dos elementos finitos Boca - Câncer Mandibulotomy Finite element Optimization Miniplates CNPQ::ENGENHARIAS::ENGENHARIA MECANICA |
description |
Currently, cancer is still the cause of high death rates worldwide. Therefore, researchers are engaged in prevention and early diagnosis of this malignant disease that affects millions of people. Specifically in Brazil, it is recognized as a public health problem. Despide all efforts, the incidence of oral cancer in particular, is most often diagnosed in advanced stages. The mandibulotomy technique is used for surgical access of some tumors in this region.The surgical access to the tumors can be done using miniplates with titanium screws or steel wires systems. They are used to fixate the osteotomies and provide maximum stability for an appropriate osteosynthesis. However, there are many doubts regarding the best mounting configurations and biomechanical behavior related to the mandibulotomy technique. In this work, the technique using the fixation by miniplates and screws were evaluated in two ways: numerically, by means of the finite element method, and experimentally, for both midline and paramidline cut. Statistical analysis with Scott Knott method (p = 5%) was used to evaluate the experimental stability. The experimental data were used to validate the numerical models and, in sequence, the prediction equations for stability were obtained using similitude methods. The variables were optimized using genetic algorithms to allow indicate the best models that guarantee the best stability. The settings of mini plates and screws of these optimized models were applied to numerical models of a human jaw and compared with those conventional conditions used by surgeons in terms of stress and displacement levels. Considering midline mandibulotomy and measurements of relative displacement between osteotomy sides, the CM2M4I - P1P3 model (fixed with four screws and positioned internally to the osteotomy line with two miniplates placed, one in the lower and the other one little higher, a middle region of the mandible) showed better stability when compared to the conventional surgical one. The better stability condition of paramidline osteotomy was the CP2M4I - P2P3 model (fixed with four screws positioned internally in relation to the osteotomy line, with two miniplates located in the middle region of the mandible). In parallel, the union stability of the midline and paramidline osteotomies was also evaluated using fasteners with stainless steel wire. Actually, this stainless steel wire technique is in disuse and showed lower stability when compared to the miniplates and screws technique. It s conclude that some configurations of miniplate and screws can replace the conventional models currently used by surgeons. |
publishDate |
2011 |
dc.date.none.fl_str_mv |
2011-10-03 2011-04-04 2016-06-22T18:39:30Z 2016-06-22T18:39:30Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/doctoralThesis |
format |
doctoralThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
CAIXETA, Delma Pereira. Biomechanical Evaluation of the Mandibulotomy Technique. 2011. 332 f. Tese (Doutorado em Engenharias) - Universidade Federal de Uberlândia, Uberlândia, 2011. https://repositorio.ufu.br/handle/123456789/14701 |
identifier_str_mv |
CAIXETA, Delma Pereira. Biomechanical Evaluation of the Mandibulotomy Technique. 2011. 332 f. Tese (Doutorado em Engenharias) - Universidade Federal de Uberlândia, Uberlândia, 2011. |
url |
https://repositorio.ufu.br/handle/123456789/14701 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf application/pdf application/pdf application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal de Uberlândia BR Programa de Pós-graduação em Engenharia Mecânica Engenharias UFU |
publisher.none.fl_str_mv |
Universidade Federal de Uberlândia BR Programa de Pós-graduação em Engenharia Mecânica Engenharias UFU |
dc.source.none.fl_str_mv |
reponame:Repositório Institucional da UFU instname:Universidade Federal de Uberlândia (UFU) instacron:UFU |
instname_str |
Universidade Federal de Uberlândia (UFU) |
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UFU |
institution |
UFU |
reponame_str |
Repositório Institucional da UFU |
collection |
Repositório Institucional da UFU |
repository.name.fl_str_mv |
Repositório Institucional da UFU - Universidade Federal de Uberlândia (UFU) |
repository.mail.fl_str_mv |
diinf@dirbi.ufu.br |
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