s 2 6

tems created a thin coating on dentin and significantly

e146 d e n t a l m a t e r i a l

dentin adhesive and each resin cement created 16 experimen-tal groups.

Flat dentin surfaces were created on mid-coronal dentin ofextracted mandibular third molars, then dentin surface waspolished with 320-grit silicon carbide abrasive papers.

Indirect resin composite block (Tescera, Bisco) with6 mm × 6 mm × 3 mm size was fabricated. Its surface for bond-ing to tooth was polished with silicon carbide abrasive papers.Each dentin adhesive was applied on tooth surface andresin composite overlay were luted with each resin cement.Each bonded specimen was poured in epoxy resin and sec-tioned occluso-gingivally into 1.0 mm thick slab, then furthersectioned into 1.0 mm × 1.0 mm composite-dentin beams.Microtensile bond strength was tested at a crosshead speedof 1.0 mm/min. The data were analyzed by one-way ANOVAand Duncan’s multiple comparison tests.

Results: When Choice, RelyX ARC and Bistite II were used,Clearfil SE-Bond that is a 2-step self-etching adhesive showedsignificantly higher uTBS values than 1-step self-etchingadhesive (p < 0.05). 1-step self-etching adhesive resulted in lowuTBS values coupled with all resin luting cements used in thisstudy. Clearfil SE-Bond didn’t show significant uTBS valuesthan All-Bond 2 that is a conventional 3-step dentin adhesive(p > 0.05). In SEM observation, Clearfil SE-Bond and All-Bond 2showed well formed hybrid layer and resin tag than the 1-stepself-etching adhesive.

Conclusions: The 2-step self-etching dentin adhesive, whichhas additional bonding resin is more compatible than the 1-step self-etching dentin adhesive.

doi:10.1016/j.dental.2009.11.122

44

Adper easy bond in total-etch mode on dentin

N. Karim a, V.A. Russell a, B.A. Shukla a,∗, C. Thalacker b, S.S.Velamakanni a

a 3M ESPE, St. Paul, MN, USAb 3M ESPE, Seefeld, Germany

Objectives: This study investigated the bonding efficacy ofAdperTM Easy Bond (EB, 3 M ESPE), a 7th generation adhesive,when used in total-etch (5th generation) mode on either moist(EB-TE-moist) or dry (EB-TE-dry) superficial bovine dentin. Themoist or dry condition of the tooth is after etching. The drycondition represents a product misuse scenario.

Materials and methods: A notched-edge shear method wasused to measure the shear bond strengths (SBS) to dentin(composite: FiltekTM Z250 A2, 3M ESPE). EB in standard self-etch mode and the 5th generation adhesive AdperTM SingleBond Plus (SB+, 3M ESPE) were tested as controls. Bondedspecimens were stored in water at 37 ◦C for 24 h. Half of thespecimens were then randomly selected and tested for base-line data, and the remaining half were thermocycled between5 and 55 ◦C (30 s each per cycle) and then tested after 7000

cycles.

Results: Mean (std dev) SBS in MPa and p-values (two-sample t-tests, p < 0.05) are listed in the table (n = 8).

( 2 0 1 0 ) e125–e157

Number ofcycles

EB(control)

EB-TE-moist

EB-TE-dry

SB+(control)

0 (baseline) 28.2 (4.6) 35.4 (4.3) 29.5 (9.7) 29.4 (7.5)7000 39.1 (5.2) 42.0 (2.3) 37.8 (5.3) 34.1 (5.7)p-Value, 0 vs. 7000cycles

0.001 0.002 0.052 0.188

p-Value vs.EB-TE-dry, 0 cycles

0.738 0.140 NA 0.989

p-Value vs.EB-TE-dry, 7000cycles

0.625 0.060 NA 0.198

Conclusions: None of the sample sets showed a decline inadhesion performance after thermocycling. EB-TE-dry was notstatistically different from either EB, EB-TE-moist, or SB+ ateither 0 cycles or 7000 cycles.

doi:10.1016/j.dental.2009.11.123

45

Dual-application of all-in-one adhesive improves resincement/dentin bond strength

R. Takahashi ∗, T. Nikaido, M. Ariyoshi, J. Tagami

Tokyo Medical and Dental University, Tokyo, Japan

Objectives: To evaluate the tensile bond strength (TBS) ofresin cements to bovine dentin resin-coated with all-in-oneadhesive systems.

Materials and methods: Each of the dual-cure resin cements;Link Max1, Clearfil Esthetic Cement2, Bistite II3 and ChemiaceII4 were used to bond indirect resin disks to bovine dentin notcoated with resin (control) or coated by single-application or bydual-application of an adhesive system from the same manu-facturer; G-Bond1, Clearfil Tri-S Bond2, Tokuyama Bond Force3

and Hybrid-Coat4, respectively (n = 10). After 24-h water stor-age, TBSs were measured at a crosshead speed of 2 mm/min.The results were statistically analyzed by ANOVA and Bonffer-roni’s correction (p < 0.05). The interface was observed using anSEM.

Results: Tensile bond strength to bovine dentin.

SEM observation revealed that the resin coating createdby single- and dual-application of all-in-one adhesives wereapproximately 5–7 �m and 12–14 �m in thickness, respec-tively.

Conclusions: Dual-application of all-in-one adhesive sys-

improved the bond strengths of resin cements and thus, is rec-ommended for an improved bonding performance of indirectrestorations.