| Participação em Congresso Internacional | |||
Os trabalhos tratam de questões de biomecânica do tecido ósseo em torno de implantes dentais, e são tecnologias criadas ou aperfeiçoadas aqui em Juiz de Fora. Já é a terceira vez que a Sociedade Européia de Biomecânica e a Sociedade Mundial de Engenharia e Medicina acolhem os trabalhos deste pesquisadores. Devido à credibilidade gerada, nestes anos, pelos trabalhos apresentados, o Dr. Mauro Cruz foi convidado para coordenar a seção de Odontologia, do Congresso Mundial de Biomecânica, realizado o ano passado em Munich e a do próximo ano, em Lucerna, na Suíça. Dra. Silvia Cruz, Diretora do Departamento de Ortodontia do Clinest, apresentou os trabalhos em duas conferências em Regensburg, representando o grupo de pesquisadores, a nossa cidade e o nosso país, pois, apesar de lá haver trabalhos de todo o mundo, estes dois são os únicos do Brasil. A Biomecânica é hoje uma área de muito interesse, que engloba todo o corpo humano, desde funções visíveis como o caminhar, até a estrutura do esqueleto celular, e o transporte de substâncias entre células e tecidos. O enfoque na área odontológica é fundamental para se conhecer estes processos na região facial. Este grupo de pesquisadores, o CLINEST e o NUMEC, pessoas e entidades de Juiz de Fora, têm prestado, além de um serviço à ciência, também uma divulgação das capacidades intelectuais e culturais de nossa cidade, publicando com freqüência em periódicos internacionais Qualis A, na Europa e nos Estados Unidos. Notícia publicada no Jornal Diário Regional, 3 e 4 de junho 2007. Veja abaixo os resumos dos trabalhos apresentados Nogueira FMA, Barbosa FS, Cruz M, Junqueira CP, Cruz L, Cruz S. Radiographic Image processing investigation of bony quality around dental implants. Regensburg Applied Biomechanics; 2007; Regensburg: 2007. p. 57. The purpose of this work was to evaluate the bony quality around dental implants by means of an automatic computational image processing of radiographies based on matching images. Periapical radiographies were used in the analysis. The first radiographic series were taken at the prosthesis placement, ie, no loaded implants, and the second ones at 24 months after the prosthesis placement, ie, after loading the implants. The image registers were obtained through the application of a projective transformation which parameters are achieved by means of an automatically identification of homologous points identified in two or more images. The results showed differences in the radiopacity levels of the radiographies of the processed images which could be related to bony density augmentation. This digital analysis allowed to increase the objectivity of the method to analyze the radiographies beyond the subjective criteria of personal interpretation, and to conclude that the method can be reliable enough to have clinical application. Cruz M, Barra LPS, Wassall T, Cruz S. Effect of dental implant offset on stress distribution pattern. Finite Element analysis. Regensburg Applied Biomechanics; 2007; Regensburg: 2007. p. 159. Purpose: A three-dimensional finite element analysis was conducted to evaluate and to compare the stress distribution around two prosthesis-implant systems, in which implants were arranged in either a straight-line or an offset configuration. Materials and Methods: The systems were modeled with three titanium endosseous implants placed in the pre-molar region of the mandible. The Straight System was built with three straight implants placed following a straight-line along the bone (no offset). The Angled System was built as follows: the first implant (mesial) was an angled implant inclined lingually; the center implant was straight; and the third (distal) was another angled implant inclined buccally. All of the implants platforms were arranged in a straight-line. Both systems received a metal-ceramic prosthesis whose crowns follow the pre-molar anatomy. In both systems, an axial load of 100N and a horizontal load of 20N were applied on the center of the crown of the center implant. Results: In both systems, the major stress occurred for vertical load respectively on mesial and on distal neck area of the first and third implants: 6.304MPa (VM) on the first implant for Straight System and 6.173MPa (VM) on the third for Angled System. The peak stress occurred for the minimum principal stress (S3) on the neck of the first implant for both systems at the level of -8.835MPa for the Straight System and -8.511MPa for the Angled System. Conclusion: In this analysis, the Angled System, with an intra-bone offset, did not induce a stress concentration in any point around the implants that was different from the Straight System. The stress distribution was very similar on both systems as well. Key words: dental implants, dental prostheses, finite element analysis, offset implants, angled implants |
|||
|
|
|||
|
|||