title: Occlusion of dentin tubules with antibacterial ammonium hexafluorosilicate solution for the prevention of dentin caries.
abstract: OBJECTIVE
  To evaluate the degree of penetration of an ammonium hexafluorosilicate [SiF: (NH4)2SiF6] solution containing various antibacterial agents into dentin and the depth of dentin tubule occlusion by the precipitate.
  
  
  METHODS
  Various antibacterial SiF solutions were prepared with the addition to chlorhexidine (CHX), cetylpyridinium chloride (CPC), isopropyl methylphenol (IPMP), or epigallocatechin gallate (EGCG), respectively. Two types of dentin disks were prepared from extracted teeth. One was a dentin surface covered with a smear layer, and the other treated with EDTA for 2 minutes to remove the smear layer and open dentin tubules. Then, the disks were treated with SiF solution with or without antibacterial agents for 3 minutes. The dentin surface and a longitudinally divided surface were observed with scanning electron microscopy (SEM) immediately after SiF treatment and after immersion in synthetic saliva for 7 days.
  
  
  RESULTS
  SEM photographs demonstrated that dentin tubules after treatment with SiF were occluded homogeneously and similar to those on conventional SiF treatment regardless of the addition of an antibacterial agent. However, the depth of occlusion became significantly shallower when SiF was applied to dentin specimens covered with a smear layer.
authors.affiliation: Department of Conservative Dentistry, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Shibata
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Suge
authors.forename: Kunio
authors.initials: K
authors.lastname: Ishikawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Matsuo
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000891:Anti-Infective Agents, Local / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D002327:Cariostatic Agents / Q000494:pharmacology*; D002392:Catechin / Q000031:analogs & derivatives / Q000494:pharmacology; D002594:Cetylpyridinium / Q000494:pharmacology; D002614:Chelating Agents / Q000494:pharmacology; D011232:Chemical Precipitation; D002710:Chlorhexidine / Q000494:pharmacology; D003731:Dental Caries / Q000517:prevention & control*; D003804:Dentin / Q000187:drug effects* / Q000648:ultrastructure; D004492:Edetic Acid / Q000494:pharmacology; D005459:Fluorides / Q000494:pharmacology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D010636:Phenols / Q000494:pharmacology; D012464:Saliva, Artificial / Q000494:pharmacology; D012824:Silicic Acid / Q000494:pharmacology*; D016369:Smear Layer; D013696:Temperature; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D000891:Anti-Infective Agents, Local; D000975:Antioxidants; D002327:Cariostatic Agents; D002614:Chelating Agents; D010636:Phenols; D012464:Saliva, Artificial; D012824:Silicic Acid; C004832:hexafluorosilicate; D002392:Catechin; D004492:Edetic Acid; C045651:epigallocatechin gallate; D002594:Cetylpyridinium; D005459:Fluorides; D002710:Chlorhexidine