Thermal Evolution of Na2O-K2O-CaO-SiO2-P2O5-Al2O3 Glass System, and Possible Applications as Biomedical Devices

Abstract

Bioceramics are widely used materials as filling bone and implants, which can be classified into three groups according to their reactivity with the body fluid and its interaction with the bone tissue: bioinert, resorbable or bioactive. Within the last class mentioned are bioactive glasses and glass-ceramics. One of the most researched topics in this area is based on ensuring the ability of the implant to long term survival, as well as improves its mechanical properties. Hence, glass-ceramics are produced by a controlled crystallization of a glass, which enables to obtain very small crystallite sizes, that increases considerably the mechanical resistance and durability of the material. The SiO2-CaO-P2O5-Na2O system is the most widely used for the production of bioactive glasses, which can be added to other compounds such as Al2O3 that, forming part of some crystal phase in the glass- ceramic, that can provide improved mechanical properties. In this work, two glasses were prepared starting from commercial Bioglass composition, adding potassium and aluminum. Both were included in the formulation by means of purified feldspar. Performed tests were differential thermal analysis and X-ray diffraction in order to follow up thermal transformation and to reveal the developed phases after such treatments.