Effectiveness of surface protection for resin-modified glass-ionomer materials

Objective: The purpose of this study was to evaluate the effectiveness of v arious surface treatments for resin-modified glass-ionomer restorative mate rials by determining dye uptake spectrophotometrically. Method and material s: 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. Spe cimens were divided into 15 groups. The positive and negative control speci mens remained unprotected, while the experimental specimens were protected with Heliobond light-activated bonding resin, Colorama nail varnish, or sur face coatings indicated by the manufacturers of the glass-ionomer materials . Finishing Gloss for Vitremer, Fuji Varnish for Fuji II LC, and Ketac Glaz e for Photac-Fil. The disks were immersed in 0.05% methylene blue for 24 ho urs except for the negative control group, which was immersed in deionized water. After 24 hours, the disks were removed, washed, and individually pla ced 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 up take was expressed in micrograms of dye per milliliter, and the results wer e analyzed with the Kruskal-Wallis test. Results: There were no differences in dye uptake among the 3 resin-modified glass-ionomer restorative materia ls, however, all of them required surface protection. Conclusion: The best surface protection for the 3 evaluated materials was obtained with Heliobon d light-activated bonding resin.