title: Bioactivity of calcium aluminate endodontic cement.
abstract: BACKGROUND
  Calcium aluminate endodontic cement (CAEC) developed for use in root canal therapy has been produced with additives that improve handling properties and provide higher mechanical strength than mineral trioxide aggregate (MTA) according to prior studies. The aim of this study was to evaluate the bioactivity of CAEC containing accelerating additives (A-CAEC) in comparison with MTA, both in contact with simulated body fluid (SBF) solutions.
  
  
  METHODS
  pH measurements were taken for set cement samples immersed in water or SBF solutions prepared according to the Kokubo and Rigo techniques. The surface of these materials kept in contact with SBF solutions were also evaluated by means of scanning electron microscopy, energy-dispersive X-ray analysis, and X-ray diffraction.
  
  
  RESULTS
  Because of the calcium hydroxide dissociation, MTA cement is able to release more Ca(2+) ions and results in a higher pH increase compared with A-CAEC. This behavior enhances the supersaturation of Kokubo solution, resulting in the precipitation of calcium phosphate phases on the MTA surface. On the other hand, for MTA in Rigo SBF solution, the pH value attained was higher than for the Kokubo SBF solution as a result of the Mg(2+) ion precipitation, which inhibited the calcium phosphate phase formation. For A-CAEC, the optimal precipitation conditions of calcium phosphate phases are achieved in Rigo SBF solution.
  
  
  CONCLUSIONS
  MTA and A-CAEC present bioactivity in contact with SBF solution although the composition of this solution defines the type of phase precipitated.
authors.affiliation: Institute for Research and Development, University of Vale do Paraíba, São José dos Campos, São Paulo, Brazil. ivoneregina.oliveira@gmail.com
authors.forename: Ivone Regina
authors.initials: IR
authors.lastname: Oliveira
authors.forename: Talita L
authors.initials: TL
authors.lastname: Andrade
authors.forename: Marcos
authors.initials: M
authors.lastname: Jacobovitz
authors.forename: Victor C
authors.initials: VC
authors.lastname: Pandolfelli
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry; D001826:Body Fluids / Q000737:chemistry; D002118:Calcium / Q000737:chemistry; D017610:Calcium Compounds / Q000737:chemistry*; D011232:Chemical Precipitation; D004338:Drug Combinations; D004577:Electron Probe Microanalysis; D006801:Humans; D006813:Humidity; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000737:chemistry; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010087:Oxides / Q000737:chemistry; D012387:Root Canal Filling Materials / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry; D012995:Solubility; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D017607:Aluminum Compounds; D001672:Biocompatible Materials; D017610:Calcium Compounds; D004338:Drug Combinations; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; C086631:mineral trioxide aggregate; D014867:Water; C035219:calcium aluminate; D008274:Magnesium; D002118:Calcium