In vivo study of bioactive scaffold with functional graduation for bone regeneration

Abstract

Bioresorbable polymers incorporated with ceramic nanoparticles can be used asbiomaterials because of their physico-chemical characteristics, structural versatility,bioactivity and superior mechanical properties and have attracted significant attentionto tissue engineering. Bioglass is one ceramic, which presents adequate bioactive andmechanical properties. Several techniques can be used for the production of polymersaiming at the manufacture of nano / micro fibers that seek the biomimetism of theextracellular matrix, among them, the electro-spinning technique. In this project, theinfluence of the bilayer polymer scaffold, consisting of a layer of PCL incorporated withbioglass particles, in micro and nanometric scale, and the one of PCL and chitosan,aiming for bone regeneration in critical defects in rat tibias, as well as the healing ofconnective tissue, respectively. For the morphological characterization of the materialswill be used scanning electron microscopy (SEM) and analysis of the wettability.Twenty-four male adult rats will be used in this study. Initially 3 mm diameter drillingswill be performed in the right and left tibias using serial drills and abundant irrigation.The animals will receive the bilayer bioactive scaffold in the left tibia, while in the righttibia will be filling with clot. After 02 and 06 weeks of surgery, the animals will beeuthanized and in 12 animals the tibias will be submitted to radiographic analysis andhistological and histomorphometric analyses to verify the best route of development ofthe bone regeneration due to the influence of the biomaterial. The around soft tissuewill be evaluated for the density of collagen fibers as well as the amount ofinflammatory cells present. In the remaining 12 animals, the tibias will be submitted tothe three-point flexion test to verify the influence of the biomaterial on the mechanicalproperties of the neoformed bone tissue. The data will be statistically analyzed, initiallyby means of the normality test aiming the application of the appropriate statistical test.The level of significance will be the conventional value of 5%.