IADR Abstract Archives
Evaluation of Bond Strength of Multi-Step Adhesives
Objectives: Historically multi-step adhesives have been formulated with HEMA to obtain compatibility with tooth structure. However, HEMA may have essentially negative impact on durability due to its hydrophilicity. We have developed a new 2-step type self-etch adhesive “G2-BOND Universal”. 1-PRIMER has a hydrophilic composition to improve wettability with the tooth, and 2-BOND has a HEMA-free hydrophobic composition to improve wettability with composite resin. In this study the bond strength of G2-BOND Universal was evaluated compared with other multi-step adhesives to find the impact of the HEMA formulation.
Methods: The materials used in this study were G2-BOND Universal (G2B, GC), CLEARFIL SE BOND2 (SE2, Kuraray), CLEARFIL SE PROTECT (SEP, Kuraray), Optibond FL (OFL, Kerr), OptiBond Solo Plus (OSP, Kerr) and OptiBond eXTRa Universal (OEU, Kerr). Bovine dentin surfaces were ground with 400-grit SiC paper. Adhesives were applied to the dentin surface according to manufacturer’s instructions and light cured with light within the mold. Composite resin was applied into mold and cured. Specimens were immersed in water at 37 degreeC for 24 hours (as 24h group). After 24h storage, half of the specimens were subjected to thermocycling (5-55 degreeC, 30s dwell) (as TC group). Specimens were subjected to shear bond strength (SBS) test at 1 mm/min (n=15). Data were analyzed by Tukey's test (p<0.05).
Results: SBS of G2B after 24h was the highest among 24h group, which was significantly higher than that of OEU. Even in TC group , SBS of G2B was the highest, which was significantly higher than that of SEP, OFL, OSP, and OEU. G2B has HEMA-free composition and it might be contribute to bonding durability. Therefore, it is considered that G2B showed high SBS.
Conclusions: G2B maintains high bond strength before and after thermocycling and may be expected to have stable bond strength in clinical practice.
Methods: The materials used in this study were G2-BOND Universal (G2B, GC), CLEARFIL SE BOND2 (SE2, Kuraray), CLEARFIL SE PROTECT (SEP, Kuraray), Optibond FL (OFL, Kerr), OptiBond Solo Plus (OSP, Kerr) and OptiBond eXTRa Universal (OEU, Kerr). Bovine dentin surfaces were ground with 400-grit SiC paper. Adhesives were applied to the dentin surface according to manufacturer’s instructions and light cured with light within the mold. Composite resin was applied into mold and cured. Specimens were immersed in water at 37 degreeC for 24 hours (as 24h group). After 24h storage, half of the specimens were subjected to thermocycling (5-55 degreeC, 30s dwell) (as TC group). Specimens were subjected to shear bond strength (SBS) test at 1 mm/min (n=15). Data were analyzed by Tukey's test (p<0.05).
Results: SBS of G2B after 24h was the highest among 24h group, which was significantly higher than that of OEU. Even in TC group , SBS of G2B was the highest, which was significantly higher than that of SEP, OFL, OSP, and OEU. G2B has HEMA-free composition and it might be contribute to bonding durability. Therefore, it is considered that G2B showed high SBS.
Conclusions: G2B maintains high bond strength before and after thermocycling and may be expected to have stable bond strength in clinical practice.
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