Compósito baseado em HA-βTCP-Nb2O5 estimula a Osteoindução durante o reparo de defeitos de tamanho crítico em calvária de ratos

Abstract

In the last decades great progress has been made in the development of materials that are indispensable in health due the need for recovery bone defects caused by trauma, infections and malformations, these are biomaterials. The aim of this study was to evaluate by morphological and immunohistochemical analysis if the composite based on hydroxyapatite -β-tricalcium phosphate niobium pentoxide (HA-βTCP-Nb2O5), has the property of osteoinduction. A critical size defect (8mm) was made in the calvaria of male Wistar rats. In the animals of composite group, the defect was filled with a tablet based on HA-β-TCP-Nb2O5, and controls groups (positive) the defect was filled with a tablet containing hydroxyapatite-β-tricalcium phosphate (HA-βTCP). The animals were killed after 7, 15, 30 and 45 days of observation and the samples of calvaria were collected and processed for paraffin inclusion. The serial sections positionated on different slides were immunostained with osteocalcin and stained with H&E and Azan. Tissues adjacents to the defect (periosteum, dura mater and bone) were analyzed. The composite presented osteoinductive potential demonstrated by its ability to induce intramembranous ossification in the dura mater and form immunopositive osseous blastema for osteocalcin, in periosteum. The remaining bone tissue presented growth from edges and suffered remodeling during the whole period of observation. The highest intensity of immunohistochemical staining occurred in the seventh and 30th day of observation in the areas of reshuffle, newly formed tissue, endothelial cells and osteoprogenitor cells in bone marrow. It is concluded that the composite showed osteoinductive activity.