title: The glass-ionomer phase in resin-based restorative materials.
abstract: Glass-ionomer (GI) fillers are added to restorative materials, but it is unclear if they truly react with these materials. This TEM study evaluated the existence of the GI phase in a conventional GIC (ChemFlex), a resin-modified GIC (Fuji II LC), a giomer (Reactmer Paste), a compomer (Dyract AP), and a composite (SpectrumTPH), before and after water uptake. Wafers were stored at 100% RH for 24 hrs, or in water for 7 or 84 days. ChemFlex glass particles were surrounded by 300-nm-thick silica gel layers. In Fuji II LC, we found thinner hydrogel layers (100 nm) that became thicker upon water storage. No appreciable change occurred in Reactmer Paste. Only a very thin hydrogel layer occurred in Dyract AP, and none was seen in SpectrumTPH after water storage for 84 days. We conclude that the variable extent of the GI phase is determined by differences in the resin composition of the restoratives.
authors.affiliation: Faculty of Dentistry, The University of Hong Kong, SAR, China. kfctay@hknet.com
authors.forename: F R
authors.initials: FR
authors.lastname: Tay
authors.forename: E L
authors.initials: EL
authors.lastname: Pashley
authors.forename: C
authors.initials: C
authors.lastname: Huang
authors.forename: M
authors.initials: M
authors.lastname: Hashimoto
authors.forename: H
authors.initials: H
authors.lastname: Sano
authors.forename: R J
authors.initials: RJ
authors.lastname: Smales
authors.forename: D H
authors.initials: DH
authors.lastname: Pashley
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D020770:Compomers / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D003793:Dental Restoration, Permanent; D017220:Dentin-Bonding Agents / Q000737:chemistry; D005899:Glass Ionomer Cements / Q000737:chemistry*; D020100:Hydrogels / Q000737:chemistry; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008854:Microscopy, Electron; D019279:Resin Cements / Q000737:chemistry*; D012117:Resins, Synthetic / Q000737:chemistry; D017640:Silicates / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; C410563:ChemFlex; D020770:Compomers; D003188:Composite Resins; D017220:Dentin-Bonding Agents; C088486:Dyract; C079765:Fuji II LC cement; D005899:Glass Ionomer Cements; D020100:Hydrogels; D008689:Methacrylates; D019279:Resin Cements; D012117:Resins, Synthetic; D017640:Silicates; C420128:Spectrum composite resin; C447779:reactmer bond