"Self-etching" adhesives (SEA) have become popular due to their purported simplified technique. Some early versions however did not perform well clinically long-term. Objectives: The purpose of this laboratory study was to determine the shear bond strength (SBS) to dentin of 5 newer generation SEA systems. Methods: Flat bonding sites were prepared on 100 extracted human molar teeth with 600-grit silicon carbide paper exposing dentin. The systems tested were: Clearfil SE Bond (SE), OptiBond Solo Plus Self Etch (OB), Xeno CF II (X), Tyrian SPE (T), and Adper Prompt L-Pop (LP). Following application of each adhesive system, bonded assemblies of Z-100 were prepared using a gelatin capsule matrix (n=20). 10 specimens in each group were debonded after water storage for 24 hours at 37°C, and 10 were stored for at least 30 days followed by thermocycling for 850 cycles between water baths at 5°C and 55°C with a dwell time of 1 minute in each bath. Specimens were loaded to failure an Instron Model 1123 testing machine with a crosshead speed of 5 mm/minute. Statistical analysis included a two-way ANOVA (adhesive, time) and Tukey's post hoc test. Results: Mean SBS (MPa) were:
|
SBS-24 hours |
SBS- Storage and thermocycling |
||
|
SE |
26.4 ± 4.2* |
OB |
27.5 ± 5.7* |
|
OB |
23.5 ± 4.4*+ |
SE |
25.5 ± 4.9*+ |
|
X |
19.5 ± 4.2 + X |
LP |
21.5 ± 3.3 + |
|
T |
16.5 ± 3.7 X |
X |
20.4 ± 2.2 + |
|
LP |
15.3 ± 3.3 X |
T |
19.2 ± 6.4 + |
Both adhesive system and storage time were significant factors (p<0.05). Groups connected the same symbols are statistically similar (p>0.05). Conclusions: There are significant differences in the in-vitro dentin SBS among the SEA materials tested. Water storage and thermocycling did not significantly degrade the SBS for the materials in this study. Supported by the Health Future Foundation.