title: A comparative study of selected properties of ProRoot mineral trioxide aggregate and two Portland cements.
abstract: OBJECTIVE
  To compare solubility, microhardness and radiopacity of ProRoot mineral trioxide aggregate (MTA) with two Portland cements (PC: CEM I and CEM II).
  
  
  METHODS
  Solubility: for standardized samples (n = 12/group) ring moulds were filled with the cements. These samples were immersed in double-distilled water for 1 min, 10 min, 1 h, 24 h, 72 h, and 28 days. Mean loss of weight was determined. Microhardness: five samples of each cement were produced. All samples were loaded with a diamond indenter point with a weight of 100 g for 30 s. Radiopacity: five samples per cement were produced. These samples were tested according to the ISO standards to compare their radiodensity to that of an aluminium step wedge (1-9 mm). Differences between the three materials with respect to their solubility, microhardness and radiopacity were analysed using ANOVA and Student-Newman-Keuls.
  
  
  RESULTS
  After 28 days MTA was of low solubility (0.78%) compared with CEM I (31.38%) and CEM II (33.33%). At exposure times >1 min the two PCs were significantly more soluble than MTA (P < 0.05). The microhardness for MTA was significantly higher (39.99 HV; P < 0.001) compared with the two PC (CEM I: 16.32 HV; CEM II: 13.51 HV). MTA was significantly more radiopaque (5.34 mm Al) than CEM I (3.32 mm Al) and CEM II (2.52 mm Al) (P < 0.05), whereas CEM I was significantly more radiopaque than CEM II (P < 0.05).
  
  
  CONCLUSIONS
  Mineral trioxide aggregate displayed superior material properties than both Portland cements.
authors.affiliation: Department of Orthodontics, University of Münster, Münster, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Danesh
authors.forename: T
authors.initials: T
authors.lastname: Dammaschke
authors.forename: H U V
authors.initials: HU
authors.lastname: Gerth
authors.forename: T
authors.initials: T
authors.lastname: Zandbiglari
authors.forename: E
authors.initials: E
authors.lastname: Schäfer
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry*; D017610:Calcium Compounds / Q000737:chemistry*; D003738:Dental Cements / Q000737:chemistry*; D004338:Drug Combinations; D006244:Hardness; D010087:Oxides / Q000737:chemistry*; D012387:Root Canal Filling Materials / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D012995:Solubility
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