Addition of Grape Seed Extract Renders Phosphoric Acid a Collagen-stabilizing Etchant.

Area of Science:

• Biomaterials Science
• Dental Materials Science
• Adhesive Dentistry

Background:

• Grape seed extract (GSE), rich in proanthocyanidins, protects demineralized dentin collagen from degradation.
• Proanthocyanidins can interfere with resin polymerization, necessitating a separate GSE application and rinse step, complicating dental procedures.
• Developing a combined etching and collagen protection method is desirable to simplify clinical application.

Purpose of the Study:

• To investigate the feasibility of combining grape seed extract (GSE) treatment with phosphoric acid etching.
• To develop and evaluate novel collagen-cross-linking dental etchants.
• To determine optimal conditions for simultaneous dentin etching and collagen stabilization.

Main Methods:

• Fourier-transformed infrared spectroscopy and digestion assays were used to assess collagen protection.
• Micro-Raman spectroscopy evaluated the effect of phosphoric acid concentration on etching.
• Scanning and transmission electron microscopy examined the penetration of phosphoric acid and GSE.

Main Results:

• GSE treatment (5-20% phosphoric acid, 30 sec) rendered demineralized dentin collagen resistant to bacterial collagenase digestion.
• Formulations with 20% phosphoric acid resulted in overetching and unsynchronized penetration of phosphoric acid and GSE.
• GSE addition stabilized phosphoric acid as a collagen-protecting etchant, with optimal concentrations below 20%.

Conclusions:

• Combining grape seed extract (GSE) with phosphoric acid creates a collagen-stabilizing etchant.
• Simultaneous dentin etching and collagen cross-linking simplifies dental bonding procedures.
• Further research should focus on phosphoric acid concentrations below 20% for optimal performance.