Hydroxyapatite based for bone tissue engineering: innovation and new insights in 3D printing technology

Hydroxyapatite, both synthetic and natural, has become a popular composite material in bone tissue engineering because it is very similar to the structure and properties of bone. In bone implants, hydroxyapatite is widely used as a coating for conventional implant materials such as titanium. This combination even continues to innovate with the addition of one or more other elements such as iron, strontium, cerium, boron nitride, manganese, tannin, wollastonite, simvastatin, and others. This reinforcement improves mechanical properties and antibacterial and corrosion resistance. In bone filler, hydroxyapatite-based filler combined with other elements, one or more elements, can be an innovation for strengthening, and type of filler, powder, agarose, gel, paste, or nanocomposite. Strengthening with doping, such as gadolinium and iron, as well as the method of making bone filler, also affects its mechanical and biological strength. The important characteristics of HA based for high performance may benefit in new prospects and challenges for bone tissue engineering. The use of 3D printing technology is an innovation in manufacturing HA-based scaffolds and one of the advantages that can provide personalized bone regeneration. Natural HA has a better capacity for scaffolds compared to synthetics. Optimizing the HA function for scaffolds can be done by adding natural polymer materials such as starch, ginger, and curcumin.