Effect of graded composite zirconia-hydroxyapatite on viability of rat osteoblast cells cultured in vitro / 中华创伤杂志

ABSTRACT

Objective To evaluate the effect of a novel orthopedic biomaterial,graded composite zireonia(ZrO2)hydroxyapatite(HAP)on activity of rat osteoblast ceils(OB)cultured in vitro. Methods The pure zirconia material was used as control to measure surface roughness of the composite material that was examined by using scanning electron microscope(SEM)and X-ray diffraetometer (XRD).The rat osteoblast cells were cultured on the two materials.Alkali phosphatase(ALP)of the two groups was measured and ELISA was used to detect IL-6 and TGF-?eoncentration of the supematant of OB cells.Tumor growth factor-?(TGF-?)mRNA was detected by RT-PCR.SEM was used to observe OB cells on the two materials.The extract of the composite material was used for a eytotoxicity test to cal- culate the relative proliferation rate(RGR)and classify the toxicity.Results The surface roughness of the gradual composite materials was significantly higher than that of the control materials(P＜0.01). The ALP of the gradual material group was markedly higher than that of the control group at different in- tervals.There was significant difference of the IL-6 and TGF-?concentrations 2-4 days after culture be- tween two groups(P＜0.05,P＜0.01).The mRNA level of TGF-?of the two OB groups also showed marked statistical difference(P＜0.01).The ossification of the OB cells on the composed material was marked after 14 days.The MTT color experiments showed no statistic significance between materials group and negative group,with the toxicity at levelⅠand 0(P＜0.05).Conclusion Graded composite ZrO2 HAP can significantly promote proliferation and differentiation of OB cells cultured in vitro and has good biocompatibility.