title: Effects of ammonium hexafluorosilicate concentration on dentin tubule occlusion and composition of the precipitate.
abstract: Ammonium hexafluorosilicate [SiF: (NH(4))(2)SiF(6)] was prepared in order to overcome the tooth discoloration caused by diamine silver fluoride [AgF: (NH(3))(2)AgF] application. We employed a single concentration of SiF solution in our previous study; therefore, it is still unclear how the concentration of SiF solution affects the occlusion of dentin tubules and composition of the precipitate.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the effects of changing the concentration of SiF on its clinical use as a dentin hypersensitivity treatment.
  
  
  METHODS
  To simulate dentin tubules subject to dentin hypersensitivity, dentin disks were treated with EDTA for 2 min. Then, the disks were treated with several concentrations of SiF solution (from 100 to 19,400 ppm) for 3 min. The occlusion of dentin tubules was evaluated using scanning electron microscopy (SEM), and the composition of the precipitate formed in the tubules after SiF treatment was assessed using energy dispersive X-ray analysis (EDXA).
  
  
  RESULTS
  SEM photographs demonstrated that dentin tubules after treatment with SiF were occluded homogeneously and fully regardless of the concentration of SiF solution. The Ca/P molar ratio of the precipitate formed in dentin tubules after SiF treatment was increased with the concentration of SiF solution.
  
  
  CONCLUSIONS
  It was concluded that the capacity to occlude dentin tubules was the same regardless of the concentration of SiF solution. However, the composition of the precipitate formed in the tubules was dependent on the concentration of SiF solution.
authors.affiliation: Department of Conservative Dentistry, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15 Kuramoto, Tokushima 770-8504, Japan. suge@dent.tokushima-u.ac.jp
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Suge
authors.forename: Akiko
authors.initials: A
authors.lastname: Kawasaki
authors.forename: Kunio
authors.initials: K
authors.lastname: Ishikawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsuo
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Ebisu
mesh_terms: D064751:Ammonium Compounds; D002118:Calcium / Q000032:analysis; D011232:Chemical Precipitation; D003804:Dentin / Q000187:drug effects* / Q000648:ultrastructure; D057133:Dentin Desensitizing Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry; D003806:Dentin Permeability / Q000187:drug effects; D003807:Dentin Sensitivity / Q000188:drug therapy; D004577:Electron Probe Microanalysis; D005459:Fluorides / Q000008:administration & dosage* / Q000737:chemistry / Q000627:therapeutic use; D005460:Fluorides, Topical; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010758:Phosphorus / Q000032:analysis; D000644:Quaternary Ammonium Compounds / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry; D012824:Silicic Acid / Q000008:administration & dosage* / Q000737:chemistry; D017655:Silicon Compounds / Q000737:chemistry / Q000627:therapeutic use; D018030:Silver Compounds; D013997:Time Factors; D014075:Tooth Discoloration / Q000139:chemically induced
chemical_list: D064751:Ammonium Compounds; D057133:Dentin Desensitizing Agents; D005460:Fluorides, Topical; D000644:Quaternary Ammonium Compounds; D017655:Silicon Compounds; D018030:Silver Compounds; D012824:Silicic Acid; D010758:Phosphorus; C054375:silicon fluoride; C024822:ammonium fluoride; C035291:hexafluorosilicic acid; C024633:silver diamine fluoride; D005459:Fluorides; D002118:Calcium