title: Surface roughening of glass ionomer cements by neutral NaF solutions.
abstract: The objective of this study was to investigate the effect of repeated applications of a neutral NaF solution on the surface roughness of four conventional glass ionomer cements (GIC) (ChemFil Superior encapsulated, Fuji Cap II, Ketac-Fil and Hi Dense), three resin-modified (RM-) GIC (Fuji II LC encapsulated, Photac-Fil and Vitremer) and one polyacid-modified composite resin (PAM-C) (Dyract). Matured specimens were four times alternately eluted in water and exposed to 2% neutral NaF aqueous solutions for 1h. Control specimens were only subjected to elution in water for the same time period. After the treatment the surface roughness R(a) was determined using non-contact surface profilometry and selected samples were examined with SEM. Except for the PAM-C, R(a) increased drastically for the fluoride-treated samples compared to water-stored samples, the effect being most pronounced for the GIC. Surface roughening apparently is caused by a progressive disintegration or chemical erosion of the polysalt matrix of (RM-)GIC.
authors.affiliation: Department of Operative Dentistry, Ghent University, De Pintelaan 185, B-9000, Gent, Belgium.
authors.forename: An M J C
authors.initials: AM
authors.lastname: De Witte
authors.forename: Erna A P
authors.initials: EA
authors.lastname: De Maeyer
authors.forename: Ronald M H
authors.initials: RM
authors.lastname: Verbeeck
mesh_terms: D002484:Cementation; D005899:Glass Ionomer Cements / Q000737:chemistry* / Q000145:classification; D008422:Materials Testing / Q000379:methods*; D012969:Sodium Fluoride / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D005899:Glass Ionomer Cements; D012969:Sodium Fluoride