Thesis (M.Sc.)--Chulalongkorn University, 2011

The purpose of this study was to investigate the effects of two Thai white Portland cement mixed with bismuth oxide (Chang and Kilan brands) and white ProRoot® MTA on gene expression and alkaline phosphatase activity of human cementoblast-like cell lines. Human cementoblast-like cell lines were exposed to material extracts for 1, 3, and 7 days. The expression of alkaline phosphatase, bone sialoprotein, type I collagen and osteocalcin were examined by quantitative real time polymerase chain reaction. Alkaline phosphatase activity was determined by enzymatic assay. Differences in relative expression ratio and alkaline phosphatase activity were analyzed by Kruskal-Wallis test (p < 0.05). Chang statistically significantly upregulated alkaline phosphatase at days 1 and 3 and white ProRootÒ MTA stimulated alkaline phosphatase at day 3. All materials significantly stimulated bone sialoprotein at day 3 and Kilan also upregulated bone sialoprotein at day 7. Both Chang and Kilan significantly increased type I collagen expression at day 1 but gene expression of osteocalcin was significantly decreased by all materials at days 3 and 7. In addition, Chang and Kilan statistically significantly induced alkaline phosphatase activity more than white ProRoot® MTA and control at days 3 and 7. In conclusion, this study of human cementoblast-like cell lines showed that Chang induced alkaline phosphatase and bone sialoprotein expression in a similar manner to white ProRoot® MTA. Kilan could not upregulate alkaline phosphatase but could increase more bone sialoprotein expression than Chang and white ProRoot® MTA. Alkaline phosphatase activity could be upregulated by Chang and Kilan but not by white ProRoot® MTA.