title: Effect of resin application time on bond strength of polymer substrate repaired with particulate filler composite.
abstract: Four different polymeric substrates were treated with unfilled intermediate resin (IMR) for various lengths of time (15 s, 3 min, 1 h, 24 h, and 2 weeks) to find out the effect of IMR treating time on shear bond strength between the substrate and a particulate filler composite. The IMR used in the study was a diacrylate monomer resin and the particulate filler composite was added on it. Two of the tested substrates were fiber-reinforced composites (FRCs). Two other substrates were cross-linked bisphenol-A-glycidyl dimethacrylate/triethyleneglycol dimethacrylate (BisGMA/TEGDMA) substrate and linear polymethylmethacrylate substrate. The bond strength of the particulate filler composite to the BisGMA/TEGDMA substrate was significantly higher compared to the other substrates (p<0.001). A correlation between increasing shear bond strength and longer treating time were found with the BisGMA/TEGDMA substrates (r=0.594, p<0.001) whereas no correlation was found with the other substrates. Prolonging of IMR treating time enhanced the BisGMA/TEGDMA substrate bond strength to the particulate filler composite but it had no clear effect on the bond strength of other substrates.
authors.affiliation: Department of Prosthetic Dentistry and Biomaterials Research, Institute of Dentistry, University of Turku, Turku, Finland. timo.kallio@saunalahti.fi
authors.forename: T T
authors.initials: TT
authors.lastname: Kallio
authors.forename: T M
authors.initials: TM
authors.lastname: Lastumäki
authors.forename: P K
authors.initials: PK
authors.lastname: Vallittu