title: The effect of dentin adhesive and cure mode on film thickness and microtensile bond strength to dentin in indirect restorations.
abstract: This study evaluated the influence of dentin adhesive application technique (pre-curing vs non precuring) on microtensile bond strength (microTBS) to dentin and adhesive layer thickness in indirect resin restorations. Seven proprietary dentin adhesives were tested, including one-step and multistep products. Experimental groups included adhesive pre-cure (PC) with a halogen light source and no pre-cure (NPC) prior to resin cement insertion. Thirty caries-free molars received an MO inlay preparation. Inlays made with Tetric Ceram resin composite were cemented using a dual-cured resin luting agent. Prior to inlay cementation, each tooth was treated with one dentin bonding agent, using pre-cure (PC) or no pre-cure (NPC). After storage in distilled water at 37 degrees C for 24 hours, the teeth were sectioned along their long axis to produce serial sticks for microtensile bond strength testing at 0.5 mm/minute. The results were subjected to statistical analysis by one-way and two-way analysis of variance (ANOVA) and Tukey's multiple comparison test (p < or = 0.05). For the film thickness evaluation, 10 additional teeth were restored and sectioned mesiodistally. The thickness of the adhesive layer was evaluated by SEM at 1000x magnification at the pre-selected locations. The microTBS varied from 11.7 +/- 4.5 MPa to 43.4 +/- 9.8 MPa. The effect of pre-curing the adhesive was material specific. No adhesive layer was visualized for the adhesives used without the pre-curing step. The thickness of the adhesive layer for the pre-cured groups varied according to the different areas analyzed.
authors.affiliation: Department of Dental Clinic, Faculty of Dentistry, Federal University of Bahia, Salvador, BA, Brazil. jacinta@ufba.br
authors.forename: Maria Jacinta Moraes
authors.initials: MJ
authors.lastname: Coelho Santos
authors.forename: Maria Fidela Lima
authors.initials: MF
authors.lastname: Navarro
authors.forename: Laura
authors.initials: L
authors.lastname: Tam
authors.forename: Dorothy
authors.initials: D
authors.lastname: McComb
mesh_terms: D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate / Q000528:radiation effects; D003188:Composite Resins; D001840:Dental Bonding / Q000379:methods*; D003799:Dental Stress Analysis; D017220:Dentin-Bonding Agents / Q000528:radiation effects*; D006244:Hardness / Q000528:radiation effects; D006801:Humans; D007284:Inlays; D008027:Light; D008422:Materials Testing; D008689:Methacrylates / Q000528:radiation effects; D008855:Microscopy, Electron, Scanning; D008963:Molar; D044367:Phase Transition; D019279:Resin Cements / Q000528:radiation effects*; D018709:Statistics, Nonparametric; D013718:Tensile Strength / Q000528:radiation effects
chemical_list: D003188:Composite Resins; D017220:Dentin-Bonding Agents; C420130:Excite cement; C103360:High-Q-Bond; D008689:Methacrylates; C451600:OptiBond Solo Plus; C500960:OptiBond Solo Plus Self-Etch; D019279:Resin Cements; C425844:Scotchbond Multi-Purpose Plus; C078484:Syntac dentine adhesive; C121818:Tetric ceram; C115612:single bond; D017438:Bisphenol A-Glycidyl Methacrylate