title: Analysis of differential artificial ageing of the adhesive interface produced by a two-step etch-and-rinse adhesive.
abstract: This study was performed to evaluate the effects of different in vitro ageing techniques on the dentine-bonded interface produced by a two-step etch-and-rinse adhesive. Composite build-ups were bonded to sectioned human molars using XP BOND and cut into non-trimmed dentine-composite beams for microtensile testing. Beams were assigned to one of the following storage conditions: (i) artificial saliva, 24 h (control); (ii) 10% sodium hypochlorite (NaOCl), 1 h; (iii) 10% NaOCl, 3 h; (iv) 60,000 thermal cycles, 2 months; (v) artificial saliva, 2 months; (vi) 60,000 thermal cycles, 6 months; and (vii) artificial saliva, 6 months. Beams were then pulled until failure and bond strength was calculated. Additional specimens were examined to investigate interfacial nanoleakage expression. NaOCl solution significantly reduced bonding compared with the control (group 2 = group 3 < group 1); and thermocycling reduced the bond strength in comparison to specimens stored for the same time-period in artificial saliva (group 4 < group 5; group 6 < group 7). Artificial ageing affected bond strength only after 6 months of storage (group 7 < group 5 = group 1). Increased nanoleakage was found under all ageing conditions in comparison with controls. NaOCl solution is a rapid and reliable in vitro ageing method for examining the durability of the adhesive interface produced by two-step etch-and-rinse adhesive systems.
authors.affiliation: Department of Restorative Dentistry, Federal University of Ceará, Fortaleza, CE, Brazil.
authors.forename: Vicente P A
authors.initials: VP
authors.lastname: Saboia
authors.forename: Francisco C F A
authors.initials: FC
authors.lastname: Silva
authors.forename: Fernando
authors.initials: F
authors.lastname: Nato
authors.forename: Annalisa
authors.initials: A
authors.lastname: Mazzoni
authors.forename: Milena
authors.initials: M
authors.lastname: Cadenaro
authors.forename: Giovanni
authors.initials: G
authors.lastname: Mazzotti
authors.forename: Marcelo
authors.initials: M
authors.lastname: Giannini
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Breschi
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000268:Adhesiveness; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003763:Dental Leakage / Q000145:classification; D003764:Dental Materials / Q000737:chemistry*; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D011108:Polymers / Q000737:chemistry; D012464:Saliva, Artificial / Q000737:chemistry; D012973:Sodium Hypochlorite / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013718:Tensile Strength; D013997:Time Factors
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; C444701:Filtek Z250; D011108:Polymers; D012464:Saliva, Artificial; C532387:XP-Bond; D012973:Sodium Hypochlorite