title: Comparative physicochemical and biocompatible properties of radiopaque dicalcium silicate cement and mineral trioxide aggregate.
abstract: BACKGROUND
  The purpose of this study was to comparatively examine physicochemical and biocompatible properties of 20 wt% bismuth oxide (Bi(2)O(3))-containing dicalcium silicate cement and white-colored mineral trioxide aggregate (WMTA).
  
  
  METHODS
  The radiopacity, setting time, diametral tensile strength, pH value, morphology, and phase composition of the cements with and without Bi(2)O(3) were measured after mixing powders with water. Cement biocompatibility was evaluated by incubating the cement specimens with MG63 human osteoblast-like cells.
  
  
  RESULTS
  The addition of Bi(2)O(3) to the cement led to a significant increase (p < .05) in the setting time of 24 minutes. It was accompanied by a small decrease in the pH value but without adversely affecting diametral tensile strength. The radiopacity value of the Bi(2)O(3)-containing cement was equivalent to 7.3 mm of aluminum, which was significantly higher (p < 0.05) than pure cement without Bi(2)O(3) (1.1 mm of aluminum) but lower (p < .05) than WMTA (9.3 mm of aluminum). However, it was greater than 3 mm of aluminum, which is the value recommended by ISO 6876/2001 standards. MG63 cell viability cultured on Bi(2)O(3)-containing cement was higher than that cultured on WMTA at all culture times.
  
  
  CONCLUSIONS
  The dicalcium silicate cement with 20 wt% Bi(2)O(3) showed shortened setting time and good biocompatibility and thus may have the potential to be a root-end filling material alternative to MTA.
authors.affiliation: Department of Dental Laboratory Technology, Central Taiwan University of Science and Technology, Taichung City, Taiwan.
authors.forename: Ting-Yi
authors.initials: TY
authors.lastname: Chiang
authors.forename: Shinn-Jyh
authors.initials: SJ
authors.lastname: Ding
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry* / Q000633:toxicity; D000704:Analysis of Variance; D001672:Biocompatible Materials / Q000737:chemistry / Q000633:toxicity; D001729:Bismuth / Q000737:chemistry* / Q000633:toxicity; D017610:Calcium Compounds / Q000737:chemistry* / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003287:Contrast Media / Q000737:chemistry* / Q000633:toxicity; D003799:Dental Stress Analysis; D004338:Drug Combinations; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D010006:Osteoblasts / Q000187:drug effects*; D010087:Oxides / Q000737:chemistry* / Q000633:toxicity; D012387:Root Canal Filling Materials / Q000737:chemistry* / Q000633:toxicity; D012823:Silicate Cement / Q000737:chemistry* / Q000633:toxicity; D017640:Silicates / Q000737:chemistry* / Q000633:toxicity; D018709:Statistics, Nonparametric; D013718:Tensile Strength
chemical_list: D017607:Aluminum Compounds; D001672:Biocompatible Materials; D017610:Calcium Compounds; D003287:Contrast Media; D004338:Drug Combinations; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; C086631:mineral trioxide aggregate; D012823:Silicate Cement; C033301:bismuth oxide; D001729:Bismuth