Application Modes Affect Two Universal Adhesive Systems' Nanoleakage Expression and Shear Bond Strength.

Area of Science:

• Dental Materials Science
• Adhesive Dentistry

Background:

• Dentin bonding systems are crucial for modern restorative dentistry.
• Evaluating the performance of universal adhesives in different etching modes is essential for clinical application.

Purpose of the Study:

• To compare the shear bond strength and nanoleakage of CLEARFIL Universal Bond Quick and Tetric N-Bond when applied in self-etch and total-etch modes.
• To assess the stability and efficacy of these universal adhesives on dentin substrates.

Main Methods:

• 100 human premolar teeth were divided into four groups based on adhesive system (Universal Bond Quick, Tetric N-Bond) and etching mode (self-etch, total-etch).
• Shear bond strength (n=15) and nanoleakage (n=10) were evaluated using standardized protocols.
• Statistical analysis included one-way ANOVA and Kruskal-Wallis tests.

Main Results:

• Tetric N-Bond in self-etch mode exhibited the highest significant shear bond strength.
• No significant differences in shear bond strength were found between Tetric N-Bond total-etch, Universal Bond Quick self-etch, and Universal Bond Quick total-etch groups.
• Self-etch application of both systems resulted in no nanoleakage, unlike the total-etch mode which showed silver nitrate deposits.

Conclusions:

• Both Universal Bond Quick and Tetric N-Bond demonstrate superior nanoleakage performance in self-etch mode.
• Universal Bond Quick maintains stable shear bond strength regardless of the etching mode.
• Tetric N-Bond shows a significant decrease in bond strength in total-etch mode but achieves optimal strength in self-etch mode.