title: Multi-component bioactive glasses of varying fluoride content for treating dentin hypersensitivity.
abstract: OBJECTIVE
  Dentin hypersensitivity (DH) is a commonly occurring dental condition, and bioactive glasses (BG) are used in dentifrice formulations for treating DH by forming a surface layer of hydroxycarbonate apatite (HCA) on the tooth, thereby occluding exposed dentinal tubules. Fluoride-containing BG, however, form fluorapatite, which is more stable toward acid attack, and provide a more sustainable option for treating DH.
  
  
  METHODS
  Melt-derived multi-component BG (SiO(2)-P(2)O(5)-CaO-CaF(2)-SrO-SrF(2)-ZnO-Na(2)O-K(2)O) with increasing CaF(2)+SrF(2) content (0-32.7 mol%) were prepared. Apatite formation, occlusion of dentinal tubules in dentin discs and ion release in Tris buffer were characterized in vitro over up to 7 days using X-ray diffraction, infrared spectroscopy, scanning electron microscopy and inductively coupled plasma emission spectroscopy.
  
  
  RESULTS
  The fluoride-containing bioactive glasses formed apatite from as early as 6h, while the fluoride-free control did not form apatite within 7 days. The glasses successfully occluded dentinal tubules by formation of apatite crystals and released ions such as fluoride, strontium and potassium.
  
  
  CONCLUSIONS
  Fluoride significantly improved apatite formation of the BG, allowing for treatment of DH by occlusion of dentinal tubules. The BG also released therapeutically active ions, such as strontium and fluoride for caries prevention, zinc for bactericidal properties and potassium, which is used as a desensitizing agent in dentifrices.
authors.affiliation: Adult Oral Health, Institute of Dentistry, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Turner Street, London E1 2AD, UK.
authors.forename: Eilis
authors.initials: E
authors.lastname: Lynch
authors.forename: Delia S
authors.initials: DS
authors.lastname: Brauer
authors.forename: Natalia
authors.initials: N
authors.lastname: Karpukhina
authors.forename: David G
authors.initials: DG
authors.lastname: Gillam
authors.forename: Robert G
authors.initials: RG
authors.lastname: Hill
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis / Q000737:chemistry; D001031:Apatites / Q000032:analysis; D001672:Biocompatible Materials / Q000032:analysis / Q000138:chemical synthesis / Q000737:chemistry*; D002327:Cariostatic Agents / Q000032:analysis / Q000737:chemistry; D002516:Ceramics / Q000032:analysis / Q000737:chemistry; D003460:Crystallization; D003804:Dentin / Q000648:ultrastructure; D057133:Dentin Desensitizing Agents / Q000032:analysis / Q000138:chemical synthesis / Q000737:chemistry*; D004058:Diffusion; D005459:Fluorides / Q000032:analysis / Q000737:chemistry*; D005898:Glass / Q000032:analysis / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D011188:Potassium / Q000032:analysis / Q000737:chemistry; D013054:Spectrophotometry, Atomic; D013055:Spectrophotometry, Infrared; D013324:Strontium / Q000032:analysis / Q000737:chemistry; D013997:Time Factors; D014961:X-Ray Diffraction; D015032:Zinc / Q000032:analysis / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D001031:Apatites; D001672:Biocompatible Materials; D002327:Cariostatic Agents; D057133:Dentin Desensitizing Agents; D015032:Zinc; D005459:Fluorides; D011188:Potassium; D013324:Strontium