IADR Abstract Archives
Bond Strength of Adhesives to Sound vs Caries-Affected Root Dentin
Objective: The purpose of this study was to compare the micro tensile bond strength of a total etch and three self-etching systems to sound or caries affected root dentin.
Materials & Methods:
The crowns of 24 extracted human premolar teeth (sound or with extensive cervical carious lesions) were removed, the roots were sectioned and prepared to expose flat dentin surfaces with 600 grit SIC paper. These two types of root dentin substrates were treated with one of the four adhesives; Hybrid Bond (Sun Medical), Excite DCA (Ivoclar), G Bond (GC), Protect Bond (Kuraray) and composite resin build ups (Clearfil AP-X, Kuraray) were created to allow sectioning for microtensile test. After storage in 37oC water for 24 hours, the roots were sectioned through the composite resin build ups in X and Y directions to obtain bonded sticks with a cross-sectional area of 0.8±0.2mm2. The specimens were attached to Ciucchi's jig with a cyanoacrylate adhesive and μTBS test was carried out at a crosshead speed of 1mm/min. Mean bond strength values were analyzed using two-way ANOVA and independent-t tests (p<0.05).
Results:
The μTBS (Mean ± SD in MPa) are presented in Table 1.
|
Adhesive |
μTBS (Mean ± SD in MPa) |
||||
|
n |
Hybrid Bond |
Excite DCA |
G Bond |
Protect Bond |
|
|
Sound root dentin |
14 |
25.9 ± 5.1 a* |
29.5 ± 7.6 a* |
27.2± 6.8 a* |
35.7± 4.9 aµ |
|
Caries-affected root dentin |
14 |
24.9 ± 7.1 a* |
28.4 ± 2.4 a* |
24.7± 4.8 a* |
20.9± 7.5 b* |
Different superscript letters in the same column and different symbols in the same line indicate significantly different groups (p<0.05).
Conclusions:
Both self etch systems showed similar bond strength to sound or caries-affected dentin except Protect Bond. Bond strength of Protect Bond was higher than the other groups on sound dentin however this significantly decreased on caries-affected dentin.