Sol gel deposited hydroxyapatite-based coating technique on porous titanium niobium for biomedical applications: A mini review
Nur Farahiyah Mohammad, R. N. Ahmad, Nurzulaikha Rosli, M.S. Abdul Manan, Marina Marzuki, Azizah Wahi
Abstract
Research on bone tissue engineering has surprisingly increased nowadays as to improve the implantations of human bones. The artificial substitutes for bones should be osteoconductive in order for the implantation to obtain a greater longevity and prevent revision surgery. Titanium and its alloys, titanium niobium (Ti-6Al-7Nb) are well known implantable metals for their superior mechanical properties and wonderful biocompatibility. However, high young modulus of titanium with respect to the bone causes the stress shielding phenomenon to arise. The issue is generally reduced by reducing the elastic module through the introduction of interconnected porous framework. The space holder technique was acknowledged as one of the feasible manufacturing processes of porous metals to control porosity used in bone implants. On the other hand, the usage of metallic biomaterials such as titanium undergoes a series of corrosion reactions in human blood fluid. Therefore, depositing coatings such as sol gel coatings with Hydroxyapatite (HA) have been proposed due to their excellent chemical stability, control of oxidation and increased resistance to corrosion while the bone ingrowth is inclined. As a result, a successful surgery and significant bone implantations has been achieved. Therefore, the aim of this study is to summarize the fabrication and deposition of porous titanium niobium for biomedical application via bone replacements together with their advantages and limitations. Furthermore, the most significant challenges and critical issues are also highlighted for the processes and techniques.