title: X-ray diffraction analysis of mineral trioxide aggregate and Portland cement.
abstract: OBJECTIVE
  To compare the major constituents present in ProRoot mineral trioxide aggregate (MTA), ProRoot MTA (tooth coloured formula), ordinary Portland cement and white Portland cement using powder X-ray diffractometery.
  
  
  METHODS
  X-ray diffractometery of the four materials was carried out with the divergence and scatter slits set at 1 degree and the receiving slit at 0.10 mm. The scan range was set at 5-70 degrees and continuous scans for the theta-2theta range were run with a scan speed of 2 degrees min(-1). The patterns obtained were then compared with the Powder Diffraction Files (PDF) found in the International Centre for Diffraction Data database. The three strongest peaks were used for the identification of the constituents. The relative intensities were plotted against the angle 2theta and compared with the plots in the PDF.
  
  
  RESULTS
  The main constituents were found to be tricalcium silicate, tricalcium aluminate, calcium silicate, and tetracalcium aluminoferrite in all the four cements with the additional presence of Bi2O3 in ProRoot MTA and ProRoot MTA (tooth coloured formula).
  
  
  CONCLUSIONS
  The four cements had similar major constituents. Data on Portland cement may be used for the further development or modification of ProRoot MTA in order to improve its physical characteristics and expand its scope of clinical applications.
authors.affiliation: Faculty of Dentistry, Department of Restorative Dentistry, National University of Singapore, Singapore.
authors.forename: I
authors.initials: I
authors.lastname: Islam
authors.forename: H K
authors.initials: HK
authors.lastname: Chng
authors.forename: A U J
authors.initials: AU
authors.lastname: Yap
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry*; D017610:Calcium Compounds / Q000737:chemistry*; D003738:Dental Cements / Q000737:chemistry*; D004338:Drug Combinations; D010087:Oxides / Q000737:chemistry*; D012387:Root Canal Filling Materials / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D017607:Aluminum Compounds; D017610:Calcium Compounds; D003738:Dental Cements; D004338:Drug Combinations; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; C086631:mineral trioxide aggregate