Application of Hydroxyapatite Obtained by Different Techniques: Metabolism and Microarchitecture Characteristics (Review).

The literature reports on microarchitecture and metabolism characteristics of synthetic hydroxyapatite obtained by different techniques were analyzed. The direct relation between hydroxyapatite production process and its microarchitecture was stated to exist. In turn, hydroxyapatite microarchitecture largely specifies its metabolism characteristics (a number of processes related to calcium and phosphorus metabolism). Therefore, with reference to the metabolism of synthetic hydroxyapatite with various microarchitectures, we analyzed the relationship of the material under study with the immune system cells. Particular emphasis was given to the relationship of hydroxyapatite characteristics with a recipient's immune system due to the material microarchitecture. The review assessed the possible participation of cell mitochondria in synthetic hydroxyapatite metabolism. There were compared the findings of a recipient's immune system in vivo and in vitro depending on hydroxyapatite nanoscale morphology. The review conclusions emphasized the necessity for further investigations of immunologically mediated metabolism of hydroxyapatite intended for bone implants, including the development of research methods in vitro for deeper understanding of the material properties. There was demonstrated the synthetic hydroxyapatite potential in treating bone defects and specified the significance of in vivo studies to develop bone surgery and reconstructive medicine.