ABSTRACT
Objective:To investigate the effect of microgroove surfaces of titanium on the adhesion and cell cycle progression of human gingival fibroblasts(HGFs).Methods:Microgroove titanium surfaces were fabricated on silicon plate by photolithography with parallel grooves:1 5,30 and 60 μm in width and 5 μm and 1 0 μm in depth,the groups were denoted as T1 5 /5,T1 5 /1 0,T30 /5,T30 /1 0, T60 /5 and T60 /1 0,respectively.Smooth titanium surfaces (T0)were used as the controls.Surface topography were observed by ES-EM.HGFs were cultured on the microgroove surfaces.Morphology of “contact guidance”was observed by immunofluorescence tech-nique.Cell cycle distribution was analyzed by Flow cytometry.Results:HGFs on the microgroove surfaces had “contact guidance”par-allel to the microgrooves,whereas the cells on T0 were oriented randomly.T60 /1 0 group had the highest percentage of S phase cells, followed by T30 group and T1 5 group,but still higher than that in the control group.In groups with higher groove width (T60 group and T30 group),the increase of groove depth benefited the increase of S phase percentage,while in T1 5 group,the increase of groove width decreased the S phase percentage.Conclusion:Surfaces of microgrooves with different dimensions achieved “contact guidance”for the cultured HGFs.The surfaces with increasing groove width and depth benefit the cell cycle progression.
ABSTRACT
Objective:To investigate the effects of microgroove surface morphology on the adhesion and proliferation of the human gin-gival fibroblasts(HGFs).Methods:Microgroove surfaces of titanium were fabricated by photolithography with parallel grooves of 15,30 or 60 μm in width and 5 μm or 10 μm in depth.The groups of the samples were denoted as T15 /5,T15 /10,T30 /5,T30 /10,T60 /5 and T60 /10.Smooth titanium surface(T0)was used as the control.The surface topography was observed by enviroment SEM(ES-EM).HGFs were cultured on the topographically modified surfaces.Morphology was observed by SEM.Cell proliferation was examined by CCK-8 kit.Results:HGFs on the microgroove surfaces had “contact guidance”parallel to the microgrooves,whereas the cells on T0 were oriented randomly.Cell proliferation was promoted and kept for longer period on T60 /10 surface.Conclusion:Surfaces of mi-crogrooves with increasing groove width and depth may achieve “contact guidance”for HGFs and promote cell proliferation.
ABSTRACT
STATEMENT OF PROBLEM: Zirconium oxide can be a substitute to titanium as implant materials to solve the esthetic problems of dark color in the gingival portion of implant restorations. PURPOSE: This study was performed to define attachment and growth behavior of osteoblast-like cells cultured on grooved surfaces of zirconium oxide and evaluate the genetic effect of zirconium oxide surfaces using the reverse transcriptase-polymerase chain reaction (RT-PCR). MATERIAL AND METHODS: MC3T3-E1 cells were cultured on (1) commercially pure titanium discs with smooth surface (T group), (2) yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) with machined surface (ZS group), and (3) Y-TZP with 100micrometer grooves (ZG group). Cell proliferation activity was evaluated through MTT assay and cell morphology was examined by SEM. The mRNA expression of Runx2, alkaline phosphatase, osteocalcin, TGF-beta 1, IGF-1, G3PDH in E1 cells were evaluated by RT-PCR. RESULTS: From the MTT assay, after 48 hours of adhesion of MC3T3-E1 cells, the mean optical density value of T group and ZG group significantly increased compared to the ZS group. SEM images of osteoblast-like cells showed that significantly more cells were observed to attach to the grooves and appeared to follow the direction of the grooves. After 24 hours of cell adhesion, more spreading and flattening of cells with active filopodia formation occurred. Results of RT-PCR suggest that T group, ZS group, and ZG group showed comparable osteoblast-specific gene expression after 24 hours of cell incubation. CONCLUSION: Surface topography and material of implants can play an important role in expression of osteoblast phenotype markers. Zirconia ceramic showed comparable biological responses of osteoblast-like cells with titanium during a short-time cell culture period. Also, grooves influence cell spreading and guide the cells to be aligned within surface grooves.