STUDY OF SURFACE MECHANICAL PARAMETERS ON COMPOSITE BIOLOGICAL STRUCTURES BY USING NON-DESTRUCTIVE OPTICAL TESTS
"In this thesis we report a study on cortical bones by means of the analysis of their surface displacement maps. We use Digital Holographic Interferometry (DHI), a powerful non-destructive optical testing for quantifying micrometric deformations. The bone samples are considered as a biological...
| Autor: | |
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| Tipo de recurso: | tesis doctoral |
| Estado: | Versión publicada |
| Fecha de publicación: | 2019 |
| País: | México |
| Institución: | Centro de Investigaciones en Óptica |
| Repositorio: | Repositorio Institucional CIO |
| Idioma: | inglés |
| OAI Identifier: | oai:cio.repositorioinstitucional.mx:1002/1107 |
| Acceso en línea: | http://cio.repositorioinstitucional.mx/jspui/handle/1002/1107 |
| Access Level: | acceso abierto |
| Palabra clave: | info:eu-repo/classification/Autor/Holography info:eu-repo/classification/Autor/Interferometry info:eu-repo/classification/Autor/Bone Drilling info:eu-repo/classification/Autor/Non-destructive Optical Tests info:eu-repo/classification/Autor/Composite material deformations info:eu-repo/classification/Autor/Bone Strength info:eu-repo/classification/cti/1 info:eu-repo/classification/cti/22 info:eu-repo/classification/cti/2209 info:eu-repo/classification/cti/220907 |
| Sumario: | "In this thesis we report a study on cortical bones by means of the analysis of their surface displacement maps. We use Digital Holographic Interferometry (DHI), a powerful non-destructive optical testing for quantifying micrometric deformations. The bone samples are considered as a biological composite material with anisotropic properties, and as a consequence, with no linear behavior that implies a no repeatable mechanical response, even under the same mechanical excitation signals. This study is divided in two stages; first, cortical bone samples are extracted from porcine femoral diaphysis and cutted into cylinders that match the flat supports of a mechanical press in order to transmit compression loads in the physiological and overload ranges. By using a medical procedure to drill the samples, it was possible to compare the effect of bone loss volume and observe the microfractures presence around the perforations against to those non-drilled samples which were used as reference control. The results show a relationship between bone loss and compression loads that can be assumed as “lower compression values and fewer drillings create higher surface displacements, while higher compression values and more cortical drillings result in smaller surface displacements”; an opposite performance of isotropic materials. This section also proves that the high resolution of DHI gives a better understanding about the bone’s microstructural modifications, making it a viable ex-vivo technique to analyze the consequences of some medical procedures. The second section of the study aims to analyze the effect in bone strength when its organic and inorganic components are degraded independently, which simulates bone illness conditions, permitting to unveil their particular role in bone mechanical response. By employing FT-IR spectral signal in transmittance it was possible to validate the effects of demineralization and air-drying procedures implemented on cortical bovine samples that were machinated for compression tests. As in the previous stages, DHI was employed to calculate the amplitude and phase information from the cortical bone samples when are compressed under controlled loads in the physiologic and overload ranges." |
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