A. Casadei | Universidade Federal de Santa Catarina - UFSC (Federal University of Santa Catarina) (original) (raw)
Papers by A. Casadei
Materials Science Forum, 2012
The rise of human life expectancy results in the increasing of elderly population and consequentl... more The rise of human life expectancy results in the increasing of elderly population and consequently the diseases of old age, which are mostly related with bone degenerative diseases. These problems also affect young individuals, commonly due to accidents (automobile and work). This fact has stimulated the research and development of materials that can replace or regenerate the damaged bone. From the engineering view, bone is a composite material consisting of an organic matrix (collagen), reinforced by an inorganic component (hydroxyapatite). The search for a suitable material, with properties tailored to the needs of the bone metabolism, as well as the adequate way of material processing, which ensures the maintenance or improvement of their initial properties, motivated this research. In this work was developed composite materials, based on bioresorbable polymer (PLLA) and phosphocalcic nanoceramic (HA). The composites were characterized by scanning electron microscopy (microstructure) and dynamical mechanical analyses (mechanical behavior). The results indicated these materials as promising for applications in the medical and dental manufacturing devices (plates and screws) by injection molding, and also for scaffolds by rapid manufacturing, in the tissue engineering area.
Ceramic Engineering and Science Proceedings, 2009
This work reports on the production of porous ceramic-polymer scaffolds based on poli(L-lactic ac... more This work reports on the production of porous ceramic-polymer scaffolds based on poli(L-lactic acid) (PLLA) and hydroxyapatite (HA) with porosity controlled by adequate sintering conditions. The composites were prepare with three different mass fraction of PLLA/HA (90/10, 80/20, and 70/30) and two different polymer particle size range (106-212 µm and 212-300 µm). The mixture was sintered at 185ºC, since low densification degree was observed at this temperature. Different sintering times were established, based on the time to achieve partial sintering and neck formation and taking into account the reproducibility of the process. The influence of sintering time, temperature, PLLA particle size and HA content on the morphology of the scaffolds was evaluated. The scaffolds were characterized by scanning electron microscopy (SEM) and compressive tests. The results revealed that the scaffolds exhibited interconnectivity between pores, pore sizes between 100 to 300 µm and suitable compressive strength to be used in bone tissue engineering.
PLLA / Hap (90% / 10%) composite scaffolds has been manufactured by different methods. However, n... more PLLA / Hap (90% / 10%) composite scaffolds has been manufactured by different methods. However, nowadays the most cases tested use other elements besides biomaterials, such as solvents, which may leave residues inside the scaffold, or cause chemical changes in the materials, compromising the viability of them in biological environment. In this work the scaffolds were manufactured by powder sintering
Resumo. Arcabouços constituídos por materiais bioreabsorvíveis, tal como o poli(L-ácido láctico),... more Resumo. Arcabouços constituídos por materiais bioreabsorvíveis, tal como o poli(L-ácido láctico), podem ser utilizados para regeneração guiada de tecidos danificados, sendo degradados e metabolizados pelo organismo. O processo de sinterização apresenta-se como potencialmente interessante para fabricação de arcabouços tridimensionais, pois permite controlar porosidade e tamanho de poro, além de dispensar a presença de solventes orgânicos, geralmente tóxicos para o organismo. Nesse contexto, o objetivo deste trabalho foi o de fabricar arcabouços tridimensionais por meio da sinterização de PLLA e de compósitos PLLA-HA com matriz polimérica. O polímero (PLLA) foi cominuído, caracterizado por DSC e TGA e misturado mecanicamente com hidroxiapatita (HA). Posteriormente, o polímero PLLA cominuído e os compósitos PLLA-HA5, PLLA-HA10 e PLLA-HA20 (onde 5, 10 e 20 representam o percentual mássico de HA, respectivamente) foram submetidos à sinterização. Os arcabouços obtidos foram então caracter...
Materials Science Forum, 2012
The rise of human life expectancy results in the increasing of elderly population and consequentl... more The rise of human life expectancy results in the increasing of elderly population and consequently the diseases of old age, which are mostly related with bone degenerative diseases. These problems also affect young individuals, commonly due to accidents (automobile and work). This fact has stimulated the research and development of materials that can replace or regenerate the damaged bone. From the engineering view, bone is a composite material consisting of an organic matrix (collagen), reinforced by an inorganic component (hydroxyapatite). The search for a suitable material, with properties tailored to the needs of the bone metabolism, as well as the adequate way of material processing, which ensures the maintenance or improvement of their initial properties, motivated this research. In this work was developed composite materials, based on bioresorbable polymer (PLLA) and phosphocalcic nanoceramic (HA). The composites were characterized by scanning electron microscopy (microstructure) and dynamical mechanical analyses (mechanical behavior). The results indicated these materials as promising for applications in the medical and dental manufacturing devices (plates and screws) by injection molding, and also for scaffolds by rapid manufacturing, in the tissue engineering area.
Ceramic Engineering and Science Proceedings, 2009
This work reports on the production of porous ceramic-polymer scaffolds based on poli(L-lactic ac... more This work reports on the production of porous ceramic-polymer scaffolds based on poli(L-lactic acid) (PLLA) and hydroxyapatite (HA) with porosity controlled by adequate sintering conditions. The composites were prepare with three different mass fraction of PLLA/HA (90/10, 80/20, and 70/30) and two different polymer particle size range (106-212 µm and 212-300 µm). The mixture was sintered at 185ºC, since low densification degree was observed at this temperature. Different sintering times were established, based on the time to achieve partial sintering and neck formation and taking into account the reproducibility of the process. The influence of sintering time, temperature, PLLA particle size and HA content on the morphology of the scaffolds was evaluated. The scaffolds were characterized by scanning electron microscopy (SEM) and compressive tests. The results revealed that the scaffolds exhibited interconnectivity between pores, pore sizes between 100 to 300 µm and suitable compressive strength to be used in bone tissue engineering.
PLLA / Hap (90% / 10%) composite scaffolds has been manufactured by different methods. However, n... more PLLA / Hap (90% / 10%) composite scaffolds has been manufactured by different methods. However, nowadays the most cases tested use other elements besides biomaterials, such as solvents, which may leave residues inside the scaffold, or cause chemical changes in the materials, compromising the viability of them in biological environment. In this work the scaffolds were manufactured by powder sintering
Resumo. Arcabouços constituídos por materiais bioreabsorvíveis, tal como o poli(L-ácido láctico),... more Resumo. Arcabouços constituídos por materiais bioreabsorvíveis, tal como o poli(L-ácido láctico), podem ser utilizados para regeneração guiada de tecidos danificados, sendo degradados e metabolizados pelo organismo. O processo de sinterização apresenta-se como potencialmente interessante para fabricação de arcabouços tridimensionais, pois permite controlar porosidade e tamanho de poro, além de dispensar a presença de solventes orgânicos, geralmente tóxicos para o organismo. Nesse contexto, o objetivo deste trabalho foi o de fabricar arcabouços tridimensionais por meio da sinterização de PLLA e de compósitos PLLA-HA com matriz polimérica. O polímero (PLLA) foi cominuído, caracterizado por DSC e TGA e misturado mecanicamente com hidroxiapatita (HA). Posteriormente, o polímero PLLA cominuído e os compósitos PLLA-HA5, PLLA-HA10 e PLLA-HA20 (onde 5, 10 e 20 representam o percentual mássico de HA, respectivamente) foram submetidos à sinterização. Os arcabouços obtidos foram então caracter...