Assessing Collagen and Micro-permeability at the Proanthocyanidin-treated Resin-Dentin Interface

Area of Science:

• Biomaterials Science
• Dental Materials Science
• Adhesion Science

Background:

• The resin-dentin interface is crucial for the longevity of dental restorations.
• Micro-permeability and collagen integrity at this interface significantly impact restoration success.
• Current methods for assessing these properties simultaneously are limited.

Purpose of the Study:

• To develop and validate a fluorescence-based method for simultaneously evaluating micro-permeability and collagen cross-linking.
• To assess the efficacy of different chemical agents in cross-linking collagen at the resin-dentin interface.
• To correlate collagen cross-linking with reduced interfacial micro-permeability.

Main Methods:

• Three agents (GSE, EDC/NHS, GD) and a control (water) were applied to dentin surfaces.
• Teeth were restored with etch-and-rinse adhesives, and interfaces were analyzed using confocal microscopy.
• Rhodamine-B infiltration assessed micro-permeability, while collagen auto-fluorescence indicated cross-linking.

Main Results:

• Glutaraldehyde (GD) showed the highest collagen fluorescence, followed by GSE.
• Grape seed extract (GSE) significantly reduced micro-permeability, regardless of the adhesive used.
• Weak correlations were observed between micro-permeability and collagen auto-fluorescence.

Conclusions:

• Non-enzymatic cross-linking agents like GSE and GD enhance collagen auto-fluorescence.
• These agents effectively reduce interfacial micro-permeability at the resin-dentin interface.
• Collagen auto-fluorescence is a valuable indicator for assessing cross-linking and its impact on interface quality.