Stability of the Dentin-Bonded Interface Using Self-Etching Adhesive Containing Diacrylamide after Bacterial...

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Adhesive Dentistry

Background:

• Acrylamides exhibit hydrolytic stability at low pH, preserving bonded interface integrity in dental adhesives.
• Self-etching primers containing 10-methacryloyloxydecyl dihydrogen phosphate (10-MDP) are crucial for modern dental bonding.

Purpose of the Study:

• To evaluate the microtensile bond strength of self-etching primers containing 10-MDP and a diacrylamide (DEBAAP) or HEMA.
• To assess the bond strength after incubation with Streptococcus mutans biofilm to simulate oral conditions.

Main Methods:

• Formulation of acidic primers and adhesives with varying compositions (10-MDP, DEBAAP, HEMA).
• Characterization of material properties including flexural strength, modulus, toughness, water sorption/solubility, and viscosity.
• Testing of microtensile bond strength (MTBS) on human dentin before and after storage in a bacterial medium.

Main Results:

• HEMA-based materials showed higher water sorption and greater strength degradation after water storage compared to DEBAAP.
• DEBAAP-based materials exhibited greater toughness but also a more significant drop in toughness after water storage.
• The DEBAAP/HEMA primer/adhesive combination (DH) demonstrated the highest MTBS after bacterial challenge, outperforming controls.

Conclusions:

• The incorporation of a diacrylamide (DEBAAP) into self-etching adhesive systems enhances bonding stability, particularly under bacterial challenge.
• The combination of DEBAAP with HEMA in primers and adhesives offers promising results for durable dental restorations.