The effect of dentin adhesive and cure mode on film thickness and microtensile bond strength to dentin in indirect restorations.
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.
Coelho Santos
Maria Jacinta Moraes
MJ
Department of Dental Clinic, Faculty of Dentistry, Federal University of Bahia, Salvador, BA, Brazil. jacinta@ufba.br
Navarro
Maria Fidela Lima
MF
Tam
Laura
L
McComb
Dorothy
D
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
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