title: Class II composite resin restorations using glass-ionomer liners: microleakage studies.
abstract: Microleakage studies were undertaken for Class II composite resin restorations that had been lined with glass-ionomer cement using the 'sandwich' technique. Thirty freshly extracted permanent molars and premolars were mounted in polymethylmethacrylate blocks. Class II cavities were prepared using carbide burs No. 245 in a water cooled dental handpiece, (cavity box 5 x 3 x 2 mm). Specimens were divided into three groups of 10 each. Group A was restored with hybrid composite resin only, Group B with hybrid composite using a light-cured glass-ionomer liner applied to dentin only, and Group C with hybrid composite using light-cured glass-ionomer liner carried out to the cavosurface margin, (beyond the DEJ). All the specimens were thermocycled between 5 degrees C and 55 degrees C for 250 cycles for 3 hours, followed by placement in 0.5% aqueous basic fuchsin dye for 24 hours at 37 degrees C. Specimens were sectioned mesio-distally through the restorations using an Isomet apparatus. The extent of dye penetration was scored under a stereomicroscope with reference to the DEJ, (0 = no penetration, 1 = penetration to the enamel, 2 = penetration beyond the DEJ). Statistical analysis of the data showed significant differences among the means of the groups at p < 0.001. The results of this study indicate that the application of a light-cured glass-ionomer up to the cavosurface margin inhibits the microleakage of Class II restorations in vitro.
authors.affiliation: Department of Restorative Dentistry, Tufts University School of Dental Medicine, Boston, MA 02111, USA.
authors.forename: A
authors.initials: A
authors.lastname: Aboushala
authors.forename: G
authors.initials: G
authors.lastname: Kugel
authors.forename: E
authors.initials: E
authors.lastname: Hurley
mesh_terms: D001641:Bicuspid; D003188:Composite Resins; D003736:Dental Cavity Lining / Q000379:methods; D003763:Dental Leakage / Q000517:prevention & control*; D003793:Dental Restoration, Permanent / Q000379:methods*; D005899:Glass Ionomer Cements; D006801:Humans; D008963:Molar; D012394:Rosaniline Dyes; D018709:Statistics, Nonparametric
chemical_list: D003188:Composite Resins; D005899:Glass Ionomer Cements; D012394:Rosaniline Dyes