Self-curing, self-etching adhesive cement systems.

Area of Science:

• Dental Materials Science
• Polymer Chemistry
• Adhesion Science

Background:

• Self-etching, self-curing adhesives are vital in dental restorations.
• Their polymerization behavior is influenced by interactions between acidic monomers and amine initiators.
• Understanding these interactions is key to optimizing adhesive performance.

Purpose of the Study:

• To investigate the impact of acid-base reactions on the polymerization of self-etching, self-curing adhesives.
• To determine how application mode affects shear bond strength and surface morphology.
• To evaluate the overall adhesion performance of these systems.

Main Methods:

• Utilized an N,N-di(2-hydroxyethyl)p-toluene (DEPT)/dibenzoyl peroxide (BPO) redox-initiator system.
• Measured the pKa of DEPT hydrochloride and assessed polymerization rates via exotherm time.
• Tested three application protocols for dental primers (Multilink, Panavia 21) and analyzed results using shear bond strength and SEM.
• Evaluated adhesion on enamel and dentin immediately and after 24 hours.

Main Results:

• Polymerization rate was significantly influenced by amine concentration and pH.
• Agitation of Multilink primer for 15 seconds improved bond strength and smear layer removal, particularly on dentin.
• Multilink demonstrated statistically higher bond strengths than Panavia 21 on both enamel and dentin.

Conclusions:

• Acidic monomers in self-etching adhesives can adversely affect radical polymerization initiators.
• Optimizing the balance of components and application techniques is essential for achieving high bond strengths.
• Proper management of these factors leads to successful adhesion in dental applications.