title: Effectiveness of surface protection for resin-modified glass-ionomer materials.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effectiveness of various surface treatments for resin-modified glass-ionomer restorative materials by determining dye uptake spectrophotometrically.
  
  
  METHODS
  Two hundred twenty-four specimens, 4.1 mm in diameter and 2.0 mm thick, were made of 3 materials: Vitremer, Fuji II LC, and Photac-Fil Aplicap. Specimens were divided into 15 groups. The positive and negative control specimens remained unprotected, while the experimental specimens were protected with Heliobond light-activated bonding resin, Colorama nail varnish, or surface coatings indicated by the manufacturers of the glass-ionomer materials: Finishing Gloss for Vitremer, Fuji Varnish for Fuji II LC, and Ketac Glaze for Photac-Fil. The disks were immersed in 0.05% methylene blue for 24 hours except for the negative control group, which was immersed in deionized water. After 24 hours, the disks were removed, washed, and individually placed in 1 mL of 65% nitric acid for 24 hours. The solutions were centrifuged and the spectrophotometric absorbance was determined at 606 nm. The dye uptake was expressed in micrograms of dye per milliliter, and the results were analyzed with the Kruskal-Wallis test.
  
  
  RESULTS
  There were no differences in dye uptake among the 3 resin-modified glass-ionomer restorative materials; however, all of them required surface protection.
  
  
  CONCLUSIONS
  The best surface protection for the 3 evaluated materials was obtained with Heliobond light-activated bonding resin.
authors.affiliation: Piracicaba School of Dentistry, University of Campinas, São Paulo, Brazil. granatoap@yahoo.com
authors.forename: A P
authors.initials: AP
authors.lastname: Ribeiro
authors.forename: M C
authors.initials: MC
authors.lastname: Serra
authors.forename: L A
authors.initials: LA
authors.lastname: Paulillo
authors.forename: A L
authors.initials: AL
authors.lastname: Rodrigues Júnior
mesh_terms: D004396:Coloring Agents; D003188:Composite Resins; D003763:Dental Leakage / Q000517:prevention & control; D018772:Dental Marginal Adaptation; D003793:Dental Restoration, Permanent / Q000379:methods*; D005899:Glass Ionomer Cements / Q000737:chemistry*; D007764:Lacquer; D016014:Linear Models; D012117:Resins, Synthetic; D018709:Statistics, Nonparametric; D013499:Surface Properties
chemical_list: D004396:Coloring Agents; D003188:Composite Resins; C079765:Fuji II LC cement; D005899:Glass Ionomer Cements; C081144:Photac-Fil; D012117:Resins, Synthetic; C084550:Vitremer