Análise fotoelástica do uso de uma única placa para tratamento de fraturas de ângulo mandibular

• Autor(a) principal: Oliveira, Danilo Louzada de
• Data de Publicação: 2017
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USC
• Texto Completo: http://tede2.usc.br:8080/jspui/handle/tede/377
• topic: Fixação interna de fraturas; Técnicas de fixação da arcada osseodentária; Fraturas ósseas; Tecido ósseo; Internal fixation of fractures; Dental arches fixation techniques; Bone fractures; Bone tissue; CIENCIAS DA SAUDE::ODONTOLOGIA

The mandible is the second most commonly fractured bone of the maxillofacial skeleton and the angle region is the most affected. The chosen treatment and most predictable results currently is the use of internal fixation through plates and titanium screws. It is pointed out in the literature that the stability of fracture fixation is benefited when there is the use of long plates and with a locking system (Locking System). The objective of this work was to evaluate the distribution of tensions among mandibular angle fracture fixations treated by the Champy technique, throgh means of a photoelastic test. An hemi-mandible of polyurethane was reproduced in 5 models of photoelastic resin, one remained intact and the others sectioned in the region of mandibular angle representing a favorable fracture. Simulated fractures were fixed following the Champy technique, using 2.0 mm straight plates with a 1.0 millimeter-thick. The plates were fixed with mono-cortical screws of 2.0 x 6.0mm according to the system used. Thus G1, with integral jaw, G2 fixed with conventional 4-hole system plate, G3 fixed with 4-hole locking system plate, G4 fixed with conventional 7-hole system plate, G5 fixed with locking system plate of 7 holes, all plates without interval. In an Instron Universal servo-hydraulic test machine, model 4411 coupled to the polariscope, a load of 100 Newtons was applied to the first molars of each hemi-mandible, 10 times and in each application. The collected images received a number from 1 to 50, in a randomized way were analyzed qualitatively and quantitatively by two evaluators previously calibrated. After the collected data were tabulated and submitted to the distribution of normality and applied statistical tests considering p <0.05. Among the groups analyzed, there was a significant difference (p≤0.001). Comparing conventional and locking plates, in the 4-hole, there was an increase of the tension in the posterior region of the fracture and reduction in the anterior one for the locking group, in the 7-hole tension reduction in the posterior region and increase in the anterior one