title: Regulation of fluoride ion release from Na2SiF6 contained in resin based on hydrophobic siloxane layer coating.
abstract: Regulation of fluoride release from restorative resin or sealant is beneficial to patients as it will prevent the occurrence of the secondary caries. In this study, we evaluated whether or not the formation of a hydrophobic polysiloxane layer on the surface of the fluoride compound could contribute to the regulation of fluoride release from resin. First, sodium hexafluorosilicate (Na2SiF6) powder was treated with gamma-methacryloxypropyltrimethoxysilane (gamma-MPTS) and analysed with scanning electronmicroscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR) and electron spectroscopy for chemical analysis (ESCA). Analysis revealed that a hydrophobic polysiloxane layer was formed on the surface of Na2SiF6 powder. Heat treatment commonly used during gamma-MPTS treatment was not necessary for the polysiloxane layer formation on the surface of Na2SiF6 powder. Then Na2SiF6 powder treated with gamma-MPTS was loaded in bis-GMA/TEGDMA resin, immersed in distilled water and fluoride release was measured using a fluoride electrode. We found that the rate of fluoride release was significantly lower from the resin containing Na2SiF6 powder treated with c-MPTS. We concluded, therefore, that c-MPTS treatment and the resulting hydrophobic polysiloxane layer formation are very effective for the regulation of fluoride release from resin.
authors.affiliation: Department of Operative Dentistry, Okayama University Dental School, Okayama, Japan. nakabo@md.okayama-u.ac.jp
authors.forename: S
authors.initials: S
authors.lastname: Nakabo
authors.forename: Y
authors.initials: Y
authors.lastname: Torii
authors.forename: T
authors.initials: T
authors.lastname: Itota
authors.forename: M
authors.initials: M
authors.lastname: Yoshiyama
authors.forename: K
authors.initials: K
authors.lastname: Ishikawa
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002327:Cariostatic Agents / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry*; D004058:Diffusion; D004577:Electron Probe Microanalysis; D005459:Fluorides / Q000737:chemistry*; D006358:Hot Temperature; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D017736:Ion-Selective Electrodes; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D012824:Silicic Acid / Q000737:chemistry*; D012833:Siloxanes / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D002327:Cariostatic Agents; D003188:Composite Resins; D008689:Methacrylates; D011109:Polymethacrylic Acids; D012821:Silanes; D012833:Siloxanes; D014867:Water; D012824:Silicic Acid; C020946:triethylene glycol dimethacrylate; C004832:hexafluorosilicate; C017492:methacryloxypropyltrimethoxysilane; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; D005459:Fluorides