An experimental model to mimic the mechanical behavior of a scaffold in a cartilage defect

[EN] Abstract The main purpose of this thesis is the design and characterization of an experimental articular cartilage model. The in vitro model is composed of a macro and micro- porous Polycaprolactone scaffold with a Poly(Vinyl Alcohol) filling. The scaffold/hydrogel construct has been subjected...

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Detalles Bibliográficos
Autor: Vikingsson, Line Karina Alva
Tipo de recurso: tesis doctoral
Fecha de publicación:2015
País:España
Institución:Universitat Politècnica de València (UPV)
Repositorio:RiuNet. Repositorio Institucional de la Universitat Politécnica de Valéncia
Idioma:inglés
OAI Identifier:oai:riunet.upv.es:10251/53912
Acceso en línea:https://riunet.upv.es/handle/10251/53912
Access Level:acceso abierto
Palabra clave:Scaffolds, biomaterials, tissue engineering
MAQUINAS Y MOTORES TERMICOS
Descripción
Sumario:[EN] Abstract The main purpose of this thesis is the design and characterization of an experimental articular cartilage model. The in vitro model is composed of a macro and micro- porous Polycaprolactone scaffold with a Poly(Vinyl Alcohol) filling. The scaffold/hydrogel construct has been subjected to repeating number of freezing and thawing cycles in order to crosslink the hydrogel inside the scaffold's pores. The Poly(Vinyl Alcohol) resembles the growing cartilaginous tissue inside the scaffolds pores, as it gets denser and stiffer for each cycle of freezing and thawing. The in vitro model allows studying a variety of characteristics of the scaffold and hydrogel, revealing interesting features. The importance of water flow on the mechanical properties is studied, so as the influence of micro-porosity. It can be seen that the mechanical properties of the porous scaffolds are influenced in distinct ways by the hydrogel density and micro-porosity of the scaffold. The permeability of the scaffolds is studied and is seen independent of crosslinking density of the hydrogel inside the porous scaffolds. The experimental cartilage model has also been applied on a macro porous acrylic scaffold. The results show that the water has different effect on the mechanical properties, for macro, or macro and micro-porous scaffolds. The in vitro cartilage model has elastic modulus, aggregate modulus and permeability values in the same order as human articular cartilage. The model is useful to predict the mechanical behavior of porous scaffolds in vivo. A scaffold implant device for animal studies has been designed based on a previous patent of the research group, and implanted in two different in vivo trials in sheep. The results show that the fixation and anchoring to the subchondral bone improve the tissue repair and diminish alterations in the subchondral bone. ¿