Influência do poliuretano granulado derivado de Ricinus Communis no processo de reparo de defeitos ósseos

• Autor(a) principal: Sousa, Tatiana Peixoto Telles de
• Data de Publicação: 2010
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USC
• Texto Completo: http://localhost:8080/tede/handle/tede/124
• topic: POLIURETANO; REGENERAÇÃO ÓSSEA; OSTEOCONDUÇÃO; POLYURETHANE; BONE REGENERATION; OSTEOCONDUCTIVITY; CIENCIAS DA SAUDE::ODONTOLOGIA

The reconstruction of wide bone defects represents a great challenge for reconstructive plastic surgery procedures. This is because the bone defects with critical size usually heal through fibrous substitution due to deficient osteogesis in the defect site as well as for the fast growth of the connective tissue that fills the surgical bone bed, hindering the osteogenesis. To solve these problems some techniques have been developed. Among of these, the use of biomaterials has been widely studied, as a bone substitute. They presents advantages in relation to the use of autogenous bone, avoiding related problems with this procedure, such as the donor site morbidity, infections, chronic pains, among others. This work consists of the study of vegetal granulated Polyurethane (Poliquil®), derivative of the Ricinus communis as a graft for treatment of bone defects. It presents some advantages such as absence of foreign body reaction and inflammation after implant, low cost and it has vegetal origin. In order to get a general panorama, the study was carried through in two bones and two types of experimental defects to evaluate the speed of bone regeneration and the cycles of bone remodelling through the analyses of the regenerated bone architecture and its degree of mineralization as function of the time. In the first experiment defects of 1,5cm x 0,5cm were surgically made in the skull of 16 rabbits. Eight animals had its defects treated with granulated Polyurethane associated with blood clot (treated group) and 8 had its defects filled only with blood clot (control group). In the second experiment, segmental defects of 5mm were made in zygomatic arch of 16 rabbits. Eight animals were treated with guided bone regeneration using the Latex membrane associated to granulated Polyurethane as a graft (treated group) and 8 animals were not treated (control group). The natural Latex has also vegetal origin. It is derivative of the Hevea Brasiliensis and the membrane of this material was already studied as occlusive membrane giving satisfactory results. After 120 and 60 days post surgery, 4 animals of each group were euthanized in both experiments and samples of bone with the defect region were collected for microscopic and radiological analyses. The results after 60 and 120 days indicate a more advanced stage in the process of bone repair in the treated group, in both experiments, demonstrating the osteoconductivity property of the Poliquil® Polyurethane.