title: Effect of tricalcium aluminate on the properties of tricalcium silicate-tricalcium aluminate mixtures: setting time, mechanical strength and biocompatibility.
abstract: OBJECTIVE
  To prepare biphasic mixtures by adding Ca(3) Al(2) O(6) into Ca(3) SiO(5) and to evaluate the effect of Ca(3) Al(2) O(6) on physical and ex vivo biological properties of the Ca(3) SiO(5) /Ca(3) Al(2) O(6) mixtures derived from mineral trioxide aggregate (MTA).
  
  
  METHODS
  Combinations of Ca(3) SiO(5) and Ca(3) Al(2) O(6) (0, 5%, 10% and 15%) powders were mixed with deionized water. After hydration, setting time, compressive strength, ex vivo bioactivity and biocompatibility of each mixture were investigated and compared to pure Ca(3) SiO(5) .
  
  
  RESULTS
  With the addition of Ca(3) Al(2) O(6) from 0% to 15%, the initial setting time and final setting time of the Ca(3) SiO(5) /Ca(3) Al(2) O(6) mixtures decreased from 110 to 43min and from 220 to 97min, respectively (P≤0.05). However, the compressive strength increased from 6.75 to 16.20MPa after one day (P≤0.05) and from 17.73 to 29.13 Mpa after 28 days. Furthermore, the mixtures with 10% Ca(3) Al(2) O(6) or less had similar bioactivity and biocompatibility when compared to the pure Ca(3) SiO(5).
  
  
  CONCLUSIONS
  The addition of Ca(3) Al(2) O(6) into Ca(3) SiO(5) accelerated the hydration process, reduced the setting time and improved the compressive strength. Furthermore, these mixtures were bioactive and biocompatible and had a stimulatory effect on the L929 cell growth when the content of Ca(3) Al(2) O(6) was below 10%. Therefore, the mixtures with 10% Ca(3) Al(2) O(6) produced the best compromise between hydration and ex vivo biological properties.
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: W-N
authors.initials: WN
authors.lastname: Liu
authors.forename: J
authors.initials: J
authors.lastname: Chang
authors.forename: Y-Q
authors.initials: YQ
authors.lastname: Zhu
authors.forename: M
authors.initials: M
authors.lastname: Zhang
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry*; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D017610:Calcium Compounds / Q000737:chemistry*; D045424:Complex Mixtures / Q000138:chemical synthesis / Q000737:chemistry; D019245:Compressive Strength; D003799:Dental Stress Analysis; D004338:Drug Combinations; D007739:L Cells; D008422:Materials Testing; D051379:Mice; D010087:Oxides / Q000737:chemistry; D012387:Root Canal Filling Materials / Q000138:chemical synthesis / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D013997:Time Factors
chemical_list: D017607:Aluminum Compounds; D001672:Biocompatible Materials; D017610:Calcium Compounds; D045424:Complex Mixtures; D004338:Drug Combinations; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; C086631:mineral trioxide aggregate; C035219:calcium aluminate; C506393:tricalcium silicate