title: [Fluoride release and recharge properties of six restorative materials].
abstract: OBJECTIVE
  To evaluate the F(-) releasing and recharging properties of six dental restorative materials.
  
  
  METHODS
  Disc specimens 10 mm in diameter and 1 mm in thickness were prepared from 6 different dental restorative materials: Fuji VII [glass ionomer cement (GIC)], Fuji II LC (light-curing, GIC), Beautifil (giomer), Compoglass F (compomer), Charisma (composite) and Experimental I (a fluoride releasing composite), with 10 discs for each material. Specimens were dipped in 5 ml deionized water and F(-) release was detected using a fluoride-specific ion electrode every day from 1-7 days and every three days from 8-28 days. On day 28, specimens were exposed to a fluoride foam for 4 min and then dipped in water, then the F(-) concentration was detected every day for a week. The specimens were exposed to fluoride foam and fluoride release was detected repeatedly for three times.
  
  
  RESULTS
  All materials presented the highest F(-) release on the first day after dipping and the F(-) release sharply decreased after 24 h and slowly decreased after 3 days. On the first day, Fuji VII presented the highest F(-) release[(99.68±15.21) µg×cm(-2)×d(-1)], followed by Fuji II LC [(37.12±1.67) µg×cm(-2)×d(-1)], Experimental I [(22.93±1.53) µg×cm(-2)×d(-1)], Compoglass F[(15.28±0.70) µg×cm(-2)×d(-1)], Beautifil[(2.40±0.52) µg×cm(-2)×d(-1)] and Charisma[(0.11±0.02) µg×cm(-2)×d(-1)]. Within 28 days of dipping, both Fuji VII and Fuji II LC released more F(-) than other materials did(P < 0.05), followed by Compoglass F and Experimental I, and Beautifil and Charisma released the least F(-)(P < 0.01). After F(-) uptake, all materials released the highest F- on the first day and presented sharply decrease after 24 h and slowly decrease after 2 days. On the first day after F(-) uptake, Fuji VII presented the highest F(-) release (>40 µg×cm(-2) ×d(-1)), much more than other materials(P < 0.01), followed by Fuji II LC(>25 µg×cm(-2) ×d(-1)). Beautifil, Compoglass F and Experimental I were close in F(-) release value(15- 20 µg × cm(-2) × d(-1)), and Charisma showed the lowest F(-) release.
  
  
  CONCLUSIONS
  Two glass ionomers were shown to have highest capacity in F(-) release and uptake, followed by compomer and fluoride releasing composite. Composite demonstrated the lowest F(-) release and uptake and Giomer was comparable to composite in F(-) release and to compomer and fluoride releasing composite in F(-) uptake.
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Yajie
authors.initials: Y
authors.lastname: Gui
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China. Email: zhaoxinyi@fmmu.edu.cn.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Shibao
authors.initials: S
authors.lastname: Li
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Lihui
authors.initials: L
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Military Stomatology, Department of Dental Materials, School of Stomatology, The Fourth Military Medical University, Xi'an 710032, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Gong
mesh_terms: D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D020770:Compomers / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D055117:Curing Lights, Dental; D003764:Dental Materials / Q000737:chemistry*; D005459:Fluorides / Q000493:pharmacokinetics*; D005899:Glass Ionomer Cements / Q000737:chemistry; D012117:Resins, Synthetic / Q000737:chemistry; D013997:Time Factors
chemical_list: C470433:Beautifil composite resin; C084111:Charisma composite resin; C105428:Compoglass; D020770:Compomers; D003188:Composite Resins; D003764:Dental Materials; C079765:Fuji II LC cement; C493186:Fuji VII; D005899:Glass Ionomer Cements; D012117:Resins, Synthetic; D017438:Bisphenol A-Glycidyl Methacrylate; D005459:Fluorides