Bonding Durability of Two All-in-One Adhesives to dentin

Objective: To evaluate bonding durability of two all-in-one adhesive systems to dentin after long-term storage in water. Material and Method: Flat coronal dentin surfaces of extracted human molars were prepared, leaving the surrounding enamel.  Two all-in-one adhesive systems: Tri-S Bond (Kuraray Medical Co.) and G-Bond (GC Co.), were applied to both dentin and the surrounding enamel surfaces according to manufacturer's instructions.  Following resin composite (Clearfil AP-X) buildups, the bonded specimens were stored in 37 ^oC water for 24 hours (control group), 3 and 6 months.  After the designated periods of water storage, the specimens were serially sectioned perpendicular to the adhesive interface into 0.7 mm thick slabs, and then trimmed to form hour-glass configurations with a 1 mm² cross-sectional area.  The micro-tensile bond strength (mTBS) test was carried out at a crosshead speed of 1.0 mm/min.  The data were statistically analyzed using two-way ANOVA and T-test (P<0.05).

Results: Two-way ANOVA revealed that there was significant difference between materials, but not significant difference between storage periods.

mean bond strength(SD)(MPa, n=10). Same letter within the vertical rows indicates that there were no significant differences as tested by T-test (P<0.05).

Conclusion: For both adhesive systems, the mTBS to dentin were almost stable during 6 months water storage when the surrounding enamel was present.