Resorption Mechanism of Hydroxyapatite and β-Tricalcium Phosphate Coating Layer

Abstract:

Beta-tricalcium phosphate(β-TCP) coating layer is known to be resorbed much faster than hydroxyapatite(HA), however, there has been no report to explain the exact reason of these results. Eighty titanium discs, coated with HA(n=40) or β-TCP(n=40) by dip and spin coating method, were divided into 2 subgroups respectively; Dissolution(D, n=20) and osteoclast culture(C, n=20). The coated discs in D group were immersed in the cell culture media for 5 days, whereas, in C group, osteoclasts were seeded on the specimens and cultured for 5 days. After simple dissolution test, β-TCP coating layer showed much more cracks and denudation as compared to HA. In osteoclast culture group, mean area fraction of resorption pits in HA-C group was 11.62%, which was significantly higher than that of 0.73% in β-TCP-C group(p=0.001). In conclusion, the resorption mechanisms of HA and β-TCP coating layers were different each other in vitro study. The coated β-TCP was degraded mainly by dissolution and separation from implant, on the other hand, the HA coating layer was resorbed by osteoclastic activity.

• Periodical: Key Engineering Materials (Volumes 396-398)
• Pages: 81-84
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.396-398.81
• Online since: October 2008
• Authors: Kang Sik Lee, Jae Suk Chang, Jung Hwa Kim, Chang Kuk You, Hoon Kwon, Dong Ho Lee
• Keywords: Biodegradation, Dissolution, Hydroxyapatite (HAP), Osteoclast, β-Tricalcium Phosphate (β-TCP)

References

[1] R. Detsch, H. Mayr, G. Ziegler. (2007) Formation of osteoclast-like cells on HA and TCP ceramics. Acta Biomaterialia.

DOI: 10.1016/j.actbio.2007.03.014

[2] Ducheyne P, Radin Shulamith, King L. (1993) The effect of calcium phosphate ceramic composition and structure on in vitro behavior. I. Dissolution. J Biomed Materials Research; 27: 25-34.

DOI: 10.1002/jbm.820270105

[3] Maruno, S., Ban, S., Wang. T.F., Iwata, H. &Itoh, H. (1992) Properties of functionally gradient composite consisting of hydroxyapatite containing glass coated titanium and characters for bioactive implant. J. Ceram. Soc. Japan; 100: pp.362-367.

DOI: 10.2109/jcersj.100.362