Laboratory evaluation of one-component enamel/dentin bonding agents

Area of Science:

• Dental Materials Science
• Adhesive Dentistry
• Biomaterials Engineering

Background:

• Effective adhesion of dental restorative materials to tooth structure is crucial for long-term restoration success.
• One-component adhesives simplify clinical application but require careful formulation for optimal performance.
• Understanding the relationship between adhesive composition, application technique, and bond efficacy is essential.

Purpose of the Study:

• To evaluate the bonding efficacy of five commercial and one experimental one-component enamel/dentin adhesives.
• To compare shear bond strength (SBS) and marginal integrity of different adhesive systems.
• To identify key components and techniques contributing to successful dentin bonding.

Main Methods:

• Six one-component adhesives (One-Step, Primabond, Prime & Bond 2.0, Solist, Tenure Quik, and an experimental compound) were tested.
• Shear bond strength to human enamel and dentin was measured after 24-hour water storage.
• Marginal gap formation and hybrid layer thickness were evaluated on dentin cavity restorations.

Main Results:

• Shear bond strengths to enamel ranged from 23-35 MPa, and to dentin from 3.5-25 MPa.
• One-Step and the experimental adhesive demonstrated the highest dentin bond strengths and consistently gap-free restorations.
• Adhesives containing wetting monomers, dimethacrylate, and acetone performed well with a moist bonding technique, producing hybrid layers of 2-10 microns.

Conclusions:

• The formulation of one-component adhesives, particularly the inclusion of wetting monomers, polymerizable resins, and acetone, significantly impacts bonding efficacy.
• A moist bonding technique is recommended for optimal performance with suitable adhesive systems.
• Clinical success in dentin bonding is achievable with carefully selected and applied one-component adhesives.