Remineralization of mechanical loaded resin-dentin interface: a transitional and synchronized multistep process

Area of Science:

• Biomaterials Science
• Dental Materials
• Mineralization Studies

Background:

• Dentin bonding interfaces are susceptible to demineralization.
• In vitro mechanical loading is explored as a method to enhance remineralization.
• Understanding mineral and matrix gradients is crucial for evaluating remineralization efficacy.

Purpose of the Study:

• To evaluate in vitro mechanical loading tests for promoting new mineral formation at bonded dentin interfaces.
• To analyze mineral and matrix gradients to understand the remineralization process.
• To compare the effects of different loading conditions and surface treatments on dentin mineralization.

Main Methods:

• In vitro mechanical loading tests were applied to dentin specimens treated with phosphoric acid (PA) or EDTA + SB.
• Analysis of mineral and matrix gradients was performed.
• Fourier transform infrared spectroscopy (FT-FTIR) was used to assess organic components and crosslinking.
• X-ray diffraction (XRD) was used to evaluate mineral crystallinity.

Main Results:

• Phosphoric acid (PA)-treated samples showed increased mineral presence, crystallinity, and phosphate peaks with mechanical loading.
• Loading in a square waveform on PA-treated samples resulted in the highest degree of dentin mineralization.
• EDTA + SB specimens showed mineral concentration increases with hold loading, but limited crystallographic maturity.
• Increased protein crosslinking and conformational changes were observed in PA-treated specimens, suggesting intrafibrillar remineralization.

Conclusions:

• Mechanical loading, particularly with square waveform on PA-treated dentin, significantly enhances in vitro remineralization.
• The remineralization process appears to be intrafibrillar in PA-treated specimens.
• Different surface treatments and loading conditions yield varying degrees of mineral deposition and crystallographic maturity.