title: Biomineralization ability and interaction of mineral trioxide aggregate and white portland cement with dentin in a phosphate-containing fluid.
abstract: BACKGROUND
  Mineral trioxide aggregate (MTA) has been shown to be bioactive because of its ability to produce biologically compatible carbonated apatite. This study analyzed the interaction of MTA and white Portland cement with dentin after immersion in phosphate-buffered saline (PBS).
  
  
  METHODS
  Dentin disks with standardized cavities were filled with ProRoot MTA, MTA Branco, MTA BIO, white Portland cement + 20% bismuth oxide (PC1), or PC1 + 10% of calcium chloride (PC2) and immersed in 15 mL of PBS for 2 months. The precipitates were weighed and analyzed by scanning electron microscopy (SEM) and x-ray diffraction. The calcium ion release and pH of the solutions were monitored at 5, 15, 25, and 35 days. The samples were processed for SEM observations. Data were analyzed by using analysis of variance or Kruskall-Wallis tests.
  
  
  RESULTS
  Our findings revealed the presence of amorphous calcium phosphate precipitates with different morphologies. The apatite formed by the cement-PBS system was deposited within collagen fibrils, promoting controlled mineral nucleation on dentin, observed as the formation of an interfacial layer with tag-like structures.
  
  
  CONCLUSIONS
  All the cements tested were bioactive. The cements release some of their components in PBS, triggering the initial precipitation of amorphous calcium phosphates, which act as precursors during the formation of carbonated apatite. This spontaneous precipitation promotes a biomineralization process that leads to the formation of an interfacial layer with tag-like structures at the cement-dentin interface.
authors.affiliation: Postgraduate program of the Federal University of Santa Catarina, Florianopolis, Santa Catarina, Brazil.
authors.forename: Jessie F
authors.initials: JF
authors.lastname: Reyes-Carmona
authors.forename: Mara S
authors.initials: MS
authors.lastname: Felippe
authors.forename: Wilson T
authors.initials: WT
authors.lastname: Felippe
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry*; D001031:Apatites / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry*; D001729:Bismuth / Q000737:chemistry; D002021:Buffers; D002118:Calcium / Q000032:analysis; D002122:Calcium Chloride / Q000737:chemistry; D017610:Calcium Compounds / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry; D011232:Chemical Precipitation; D003094:Collagen / Q000648:ultrastructure; D003738:Dental Cements / Q000737:chemistry*; D003786:Dental Pulp Cavity / Q000648:ultrastructure; D003804:Dentin / Q000648:ultrastructure*; D004338:Drug Combinations; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010087:Oxides / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry*; D012387:Root Canal Filling Materials / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D013499:Surface Properties; D013997:Time Factors; D014961:X-Ray Diffraction
chemical_list: D017607:Aluminum Compounds; D001031:Apatites; D001672:Biocompatible Materials; D002021:Buffers; D017610:Calcium Compounds; D002130:Calcium Phosphates; D003738:Dental Cements; D004338:Drug Combinations; D010087:Oxides; D010710:Phosphates; D012387:Root Canal Filling Materials; D017640:Silicates; C086631:mineral trioxide aggregate; C030782:carboapatite; D003094:Collagen; C033301:bismuth oxide; D002122:Calcium Chloride; D002118:Calcium; D001729:Bismuth