Nfluence Of Osteoblast Function On Ultraviolet Light-treated Zirconia With Different Roughness

ObjectiveThe study examined the effect of the UV treatment of different roughness zirconia surfaces on the MC3T3-E1 osteoblast cells proliferation、differentiation、cytoskeleton spreading and the gene expression of OPG and OCN.To discuss the osseointegration of MC3T3-E1 under the condition of ultraviolet.MethodsAll the zirconia discs were randomly divided into smooth and roughened surfaces by sandblasting.Half of each groups were treated with UV light(15W)for 48h.MC3T3-E1 cells were cultured on zirconia disks which divided into 4 groups:smooth group(S),UV treated smooth group(S-UV),rough group(R),UV treated rough group(R-UV).Observed the cell proliferation by MTT assay at 3 and 5 day.The ALP activity of culltured osteoblasts was examined at 3 and 7 day.The mineralization capability of cultured osteoblasts was examined by alizarin red dye staining at 21 day.Gene expression of OPG and OCN mRNA was semiquantitatively analyzed using reverse transcriptionpolymerase chain reaction(RT-PCR)at cultured 7 and 14 day.Confocal laser scanning microscopy was observed the F-action and microstructure of the cultured osteoblasts after 1.5h and 6h of the experiment.ResultsThe data of MTT shows that all groups the R-UV was more benefit for the proliferation,and mineralization of MC3T3-E1 cell,which had big differences with the S group(P<0.05).And the same outcome was found between S-UV group and R group surfaces.The examination of ALP activity after 3 and 7 days show that S group was higher than S-UV group.There was no significant differences between UV-treated and untreated roughened surfaces.The R-UV group increased the gene expressions of OPG and OCN in a time-dependent manner(P<0.05).After cultured 1.5 h,S-UV group and R group cells begin to spread and the F-actin in R-UV group of cells was more than the other three groups but the arrangement is irregular.Cultured after 6 h,S-UV、R,R-UV groups can visible found protein structure,R-UV group showed the most entensive of the spread of the F-actin cytoskeleton.ConclusionsUnder the condition of the ultraviolet light-treated zirconia is better for the proliferation and mineralization of MC3T3-E1 cell,has a more pronounced effect on the expression of OCN and OPG.R-UV group was also benefit for the microstructure formation of the osteoblasts.The ultraviolet light-treated zirconia implants have the excellent biocompatibility and benefit for the early osseointegration.