Obtenção de hidroxiapatita para regeneração óssea via síntese pseudomórfica hidrotermal.

Abstract

Biomaterials are materials used for the replacement and regeneration of damaged bone tissue, and may be classified as metals, ceramics, polymers and composites. Hydroxyapatite (Ca10 (PO4) 6 (OH) 2) is a bioceramic widely used in bone repair it is the main component of the mineral phase of bone. It consists primarily of calcium, phosphorus and oxygen and can be synthesized by solid and wet methods of reactions. Understanding the mechanisms of obtaining this material is of utmost importance in order to ensure a material capable of perfectly fulfill its function in the human body. Thus, the influence of the synthesis time, crystallography and chemical composition of hydroxyapatite obtained were the goals of this research. The precursor for the synthesis solution was prepared from 0.5 M ammonium phosphate and ammonium hydroxide 0.75 M and subsequently reacted with three-dimensional frameworks (scaffolds) orthodontic gypsum under hydrothermal conditions (120 ° C and 2 atm) for 3 hours. At the end of the synthesis scaffolds were washed and placed in an oven at 75 ° C for 24 hours. The results of the characterization diffraction X-ray confirmed the presence of hydroxyapatite phase but also revealed the presence of β-tricalcium phosphate (β-TCP) and also calcium sulphate phase. The fluorescence X-rays detected impurities in the synthesized samples, which are: silicon, strontium and sulfur. The hydrothermal synthesis was Pseudomorphic efficient for obtaining hydroxyapatite and keeping the macrostructure scaffolds but without full purity.