In vitro mechanical stimulation promoted remineralization at the resin/dentin interface

Area of Science:

• Dental Materials Science
• Biomaterials Engineering
• Nanotechnology in Dentistry

Background:

• Teeth undergo constant mechanical stress from daily functions.
• Understanding remineralization at dentin interfaces is crucial for restorative dentistry.

Purpose of the Study:

• To investigate if mechanical loading can induce remineralization in etched and bonded dentin interfaces.
• To assess the impact of load cycling on the structural and mechanical integrity of resin-dentin bonds.

Main Methods:

• Human dentin surfaces were demineralized and treated with different bonding agents (etch-and-rinse, self-etch).
• Specimens underwent simulated mechanical loading (100,000 cycles).
• Remineralization was evaluated using Atomic Force Microscopy (AFM), nano-indentation, Raman spectroscopy, and confocal microscopy.

Main Results:

• Load cycling generally enhanced mechanical properties at the resin-dentin interface.
• Increased mineral-matrix ratio observed in loaded specimens, particularly with self-etch adhesives.
• Reduced micropermeability and nanoleakage were detected after load cycling, most significantly in self-etch bonded interfaces.

Conclusions:

• In vitro load cycling effectively promoted remineralization at resin-dentin interfaces.
• Mineral content and nanomechanical properties improved within the hybrid layer and at its base.
• Load cycling led to higher mineral concentration and reduced demineralized dentin at bonded interfaces.