5 research outputs found
Improvement of the Cell-loading Efficiency of Biomaterials by Inoculation with Stem Cell-based Microspheres, in Osteogenesis
Estudo da interação polímero/cartilagem/osso utilizando poli (ácido lático-co-ácido glicólico) e poli (p-dioxanona) em condilo femural de coelhos Study of polymer/cartilage/bone interaction using poly(lactic acid-co-glycolic acid) and poly (p-dioxanona) in femoral condyle of rabbits
Os dispositivos biorreabsorvíveis são alternativas para fixação interna das fraturas. Durante o tratamento estes dispositivos mantêm a fixação e degradam-se gradualmente não necessitando de uma cirurgia de remoção, reduzindo o custo de tratamento quando comparadas aos dispositivos metálicos. O objetivo desse trabalho foi estudar a interação polímero/tecido utilizando pinos de PLGA e PDS após implantes em coelhos Nova Zelândia. Separou-se os animais em 3 grupos os quais foram sacrificados após 3, 6 e 12 semanas de implantação e o material obtido foi submetido à análise histológica. As análises histológicas com implantes de PLGA mostraram após 3 semanas a formação de um tecido com características mesenquimatosas e com 12 semanas a formação de uma estrutura óssea madura. Já nos implantes de PDS de 3 semanas houve uma maior invasão de tecido mesenquimal comparado ao PLGA e após 12 semanas, ocorreu uma degradação avançada, com tecido proliferativo mesenquimal e ósseo. Assim, concluiu-se que ocorreram resultados positivos à resposta tecidual/implante e foi relevante a observação da ausência de células responsáveis pela resposta inflamatória. As análises demonstraram que o copolímero de PLGA apresentou propriedades osteoindutivas mais adequadas que os de PDS, apresentando biocompatibilidade aceitável para aplicação ortopédica.<br>Bioresorbable devices are alternatives for internal fixation. During the treatment, those devices maintain the fixation, degrade gradually and eliminate the need for a remove surgery, decreasing the treatment cost when compared with metallic devices. The aim of this work was to study the interaction polymer/tissue interaction using pins of PLGA and PDS implanted in New Zealand rabbits. The animals were separated in 3 groups which were sacrificed after 3, 6 and 12 weeks after implantation, and the obtained material was submitted to histological analysis. Histological analysis with PLGA implants showed after 3 weeks, the growth of a tissue with mesenchimal characteristics, after 3 weeks, with formation of mature bone aready after 12 weeks. PDS implants after 3 weeks showed a bigger invasion of mesenchimal tissue compared to PLGA and after 12 weeks an advanced degradation occurred, with proliferation of mesenchimal and bone tissue formation. It is concluded that the results are highly positive, with the relevant absence of cells responsible for inflammatory response. Analysis showed that the copolymer PLGA has better ostoinductive properties than PDS, showing biocompatibility acceptable for orthopedics application
Biomaterials in orthopaedics
At present, strong requirements in orthopaedics are still to be met, both in bone and joint substitution and in the repair and regeneration of bone defects. In this framework, tremendous advances in the biomaterials field have been made in the last 50 years where materials intended for biomedical purposes have evolved through three different generations, namely first generation (bioinert materials), second generation (bioactive and biodegradable materials) and third generation (materials designed to stimulate specific responses at the molecular level). In this review, the evolution of different metals, ceramics and polymers most commonly used in orthopaedic applications is discussed, as well as the different approaches used to fulfil the challenges faced by this medical field