Preparation of graded zirconia–CaP composite and studies of its effects on rat osteoblast cells in vitro

✍ Scribed by Renfu Quan; Disheng Yang; Jie Yan; Wei Li; Xiaochun Wu; Hongbin Wang

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 778 KB
• Volume: 29
• Category: Article
• ISSN: 0928-4931
• DOI: 10.1016/j.msec.2008.06.019

✦ Synopsis

Hydroxyapatite (HAP) has excellent biocompatibility and bone bonding ability, but it is mechanically weak and brittle. To overcome this problem, we prepared a graded composite with calcium phosphide (CaP, decomposed from HAP during sintering) coating on the surface of zirconia (ZrO 2 ) ceramics. The mechanical properties and microstructure characteristics were studied with various techniques. The biocompatibility of graded ZrO 2 -CaP composite was examined with rat osteoblast cells (OB cells) in vitro. Its effects on the production of alkaline phosphatase (ALP), Interleukin-6 (IL-6) and Growth-transforming Factor-β (TGF-β) by the OB cells were measured. The results showed that the mean tensile strength of the graded ZrO 2 -CaP composites was 17.8 MPa, the maximum bending strength was 1112.24 MPa, and K IC was 7.3-11.4 MPa m 1/2 , indicating that the composite was physically strong for use as an implant material. The ALP activity, IL-6 and TGF-β concentrations of the graded composite treated OB cells were much higher than that of the pure ZrO 2 treated group. There was no significant difference in ALP activity, the IL-6 and TGF-β concentrations between the graded ZrO 2 -CaP composite group and HAP. The cytotoxicity of the composite material to rat fibroblast cells was insignificant. The graded zirconia-CaP composite greatly facilitated the proliferation and differentiation of rat OB cells in vitro, demonstrating excellent biocompatibility.