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Operator Experience Does Not Affect the Reliability of Universal Adhesives' Bond Strength; Adhesive Type Does
The Journal of Adhesive Dentistry
|June 23, 2026
Summary
A new universal adhesive (UA) demonstrated consistent shear bond strength (SBS) in dental restorations, outperforming etch-and-rinse adhesives (ERA). UA showed reliable performance across different operator experience levels and dentin moisture conditions, indicating clinical dependability.
Area of Science:
- Dental Materials Science
- Adhesive Dentistry
- Biomaterials Engineering
Background:
- Operator experience and dentin moisture significantly influence dental adhesive performance.
- Evaluating adhesive consistency is crucial for predicting clinical reliability.
- Universal adhesives (UA) aim to simplify application while maintaining bond strength.
Purpose of the Study:
- To assess the impact of operator experience, dentin moisture condition (DMC), and adhesive type on shear bond strength (SBS).
- To evaluate the consistency of adhesive performance under varying conditions.
- To determine the clinical reliability of a universal adhesive compared to an etch-and-rinse adhesive.
Main Methods:
- Six hundred dentin surfaces were bonded by experienced dentists and novice students using a universal adhesive (UA) and an etch-and-rinse adhesive (ERA).
- Adhesive application was performed on wet, moist, and dry dentin surfaces.
- Shear bond strength (SBS) was tested after 24-hour storage; statistical analysis included boxplots and Tukey HSD.
Main Results:
- The universal adhesive (UA) exhibited significantly higher SBS (25.53 MPa dentists, 24.96 MPa students) compared to the etch-and-rinse adhesive (ERA) (17.79 MPa dentists, 13.52 MPa students).
- UA showed reduced variability in SBS across operators and dentin moisture conditions.
- Dry and moist dentin surfaces resulted in higher SBS than wet surfaces, with no significant difference between moist and dry conditions.
Conclusions:
- The tested universal adhesive (UA) demonstrated consistent and reliable shear bond strength outcomes.
- UA performance was not significantly affected by operator experience or dentin moisture condition.
- UA offers a clinically reliable alternative to etch-and-rinse adhesives, simplifying dental procedures.
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