title: Quantification of leucite concentration using X-ray diffraction.
abstract: OBJECTIVE
  This study sought to evaluate the efficacy of using an X-ray diffractometer for the determination of leucite in Finesse, Ceramco II, and IPS Empress porcelains.
  
  
  METHODS
  An internal standard, copper, was used. Two quantification methods are presented: (1) the generation of a calibration curve using peak height ratios; and (2) the generation of a calibration curve using peak area ratio.
  
  
  RESULTS
  The leucite concentration obtained from the peak height versus concentration calibration curve was observed to be statistically different from leucite concentration obtained from the peak area versus concentration calibration curve. Other information obtained from X-ray powder diffraction include the lattice parameters and volume of the unit leucite cell.
  
  
  CONCLUSIONS
  The leucite contained in the dental porcelains (Finesse, Ceramco II, and Empress) has expanded a-lattice spacings and contracted c-lattice spacings relative to standard leucite. These changes in the lattice parameters resulted in a net expansion of the leucite cell volume.
authors.affiliation: Department of Restorative Dentistry, Division of Biomaterials, Health Science Center, San Antonio, University of Texas, 7703 Floyd Curl Drive, San Antonio, TX 78284-7890, USA. ong@uthscsa.edu
authors.forename: J L
authors.initials: JL
authors.lastname: Ong
authors.forename: D W
authors.initials: DW
authors.lastname: Farley
authors.forename: B K
authors.initials: BK
authors.lastname: Norling
mesh_terms: D000538:Aluminum Silicates / Q000032:analysis* / Q000737:chemistry; D000704:Analysis of Variance; D003188:Composite Resins / Q000737:chemistry; D018360:Crystallography, X-Ray; D003776:Dental Porcelain / Q000737:chemistry*
chemical_list: D000538:Aluminum Silicates; D003188:Composite Resins; C075815:IPS-Empress ceramic; D003776:Dental Porcelain; C078519:leucite; C037884:finesse; C058233:Ceramco