title: Microtensile bond strength test and failure analysis to assess bonding characteristics of different adhesion approaches to ground versus unground enamel.
abstract: This study evaluated the bonding characteristics to ground and unground enamel obtained with different strategies. For this purpose, 24 sound third-molars were bisected mesiodistally to obtain tooth halves. A flat enamel area was delimited in the tooth sections, which were randomly distributed into 8 groups (n=6), according to the enamel condition (ground and unground) and adhesive system (Adper Single Bond 2 - SB2; Adper Prompt L-Pop - PLP; Adper Prompt - AD; Clearfil SE Bond - SE). Each system was applied according manufacturers' instructions and a 6-mm-high resin composite "crown" was incrementally built up on bonded surfaces. Hourglass-shaped specimens with 0.8 mm(2) cross-section were produced. Microtensile bond strength (μTBS) was recorded and the failure patterns were classified. Results were analyzed by two-way ANOVA and Tukey's test (α=0.05). There were no statistically significant differences among the μTBS values of SB2, PLP and AD (p>0.05). SE values were significantly lower (p0.05). There was prevalence of cohesive failure within enamel, adhesive system and resin composite for SB2. The self-etch systems produced higher incidence of cohesive failures in the adhesive system. Enamel condition did not determine significant differences on bonding characteristics for the same bonding system. In conclusion, the bonding systems evaluated in this study resulted in specific μTBS and failure patterns due to the particular interaction with enamel.
authors.affiliation: Dental Research Group, Dental School, Bandeirante University of São Paulo, SP, Brazil. vdhipolito@yahoo.com.br
authors.forename: Vinicius Di
authors.initials: VD
authors.lastname: Hipólito
authors.forename: Roberta Caroline Bruschi
authors.initials: RC
authors.lastname: Alonso
authors.forename: Marcela Rocha de Oliveira
authors.initials: MR
authors.lastname: Carrilho
authors.forename: Camillo
authors.initials: C
authors.lastname: Anauate Netto
authors.forename: Mário Alexandre Coelho
authors.initials: MA
authors.lastname: Sinhoreti
authors.forename: Mario Fernando de
authors.initials: MF
authors.lastname: Goes
mesh_terms: D003188:Composite Resins / Q000528:radiation effects; D001840:Dental Bonding / Q000379:methods*; D003738:Dental Cements; D003743:Dental Enamel / Q000648:ultrastructure; D045662:Dental Etching / Q000379:methods; D003799:Dental Stress Analysis; D006801:Humans; D055115:Light-Curing of Dental Adhesives; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements; D016369:Smear Layer; D013499:Surface Properties; D013718:Tensile Strength
chemical_list: C554641:Adper single bond 2; C438313:Clearfil SE Bond; D003188:Composite Resins; D003738:Dental Cements; C408584:Prompt L-Pop; D019279:Resin Cements