title: Gene expression of MC3T3-E1 osteoblastic cells on titanium and zirconia surface.
abstract: OBJECTIVE
  This study was performed to define attachment and growth behavior of osteoblast-like cells and evaluate the gene expression on zirconia compared to titanium.
  
  
  METHODS
  MC3T3-E1 cells were cultured on (1) titanium and (2) zirconia discs. The tetrazolium-based colorimetric assay (MTT test) was used for examining the attachment of cells. Cellular morphology was examined by scanning electron microscopy (SEM) and alkaline phosphatase (ALP) activity was measured to evaluate the cell differentiation rate. Mann-Whitney test was used to assess the significance level of the differences between the experimental groups. cDNA microarray was used for comparing the 20215 gene expressions on titanium and zirconia.
  
  
  RESULTS
  From the MTT assay, there was no significant difference between titanium and zirconia (P>.05). From the SEM image, after 4 hours of culture, cells on both discs were triangular or elongated in shape with formation of filopodia. After 24 hours of culture, cells on both discs were more flattened and well spread compared to 4 hours of culture. From the ALP activity assay, the optical density of E1 cells on titanium was slightly higher than that of E1 cells on zirconia but there was no significant difference (P>.05). Most of the genes related to cell adhesion showed similar expression level between titanium and zirconia.
  
  
  CONCLUSIONS
  Zirconia showed comparable biological responses of osteoblast-like cells to titanium for a short time during cell culture period. Most of the genes related to cell adhesion and signal showed similar expression level between titanium and zirconia.
authors.affiliation: Department of Prosthodontics, School of Dentistry, Kyung-Hee University, Seoul, Republic of Korea.
authors.forename: Soon-Hyun
authors.initials: SH
authors.lastname: Gong
authors.affiliation: Department of Oral Anatomy, Dental School, Gangneung-Wonju National University, Kangnung, Republic of Korea.
authors.forename: Heesu
authors.initials: H
authors.lastname: Lee
authors.affiliation: Department of Prosthodontics, School of Dentistry, Kyung-Hee University, Seoul, Republic of Korea.
authors.forename: Ahran
authors.initials: A
authors.lastname: Pae
authors.affiliation: Department of Prosthodontics, School of Dentistry, Kyung-Hee University, Seoul, Republic of Korea.
authors.forename: Kwantae
authors.initials: K
authors.lastname: Noh
authors.affiliation: Department of Prosthodontics, School of Dentistry, Kyung-Hee University, Seoul, Republic of Korea.
authors.forename: Yong-Moon
authors.initials: YM
authors.lastname: Shin
authors.affiliation: Department of Prosthodontics, School of Dentistry, Kyung-Hee University, Seoul, Republic of Korea.
authors.forename: Jung-Haeng
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Prosthodontics, School of Dentistry, Kyung-Hee University, Seoul, Republic of Korea.
authors.forename: Yi-Hyung
authors.initials: YH
authors.lastname: Woo
keywords: Dental implants; Osteoblast-like cells; Titanium; Zirconia; cDNA microarray