Hybridization efficiency of the adhesive/dentin interface with wet bonding

Area of Science:

• Dental Biomaterials
• Adhesive Dentistry
• Materials Science

Background:

• Dentin bonding is crucial for dental restorations.
• Current understanding of adhesive infiltration under wet bonding conditions is limited.
• The quality of the adhesive/dentin interface affects bond longevity.

Purpose of the Study:

• To compare the quality and molecular structure of adhesive/dentin (a/d) interfaces formed by wet bonding versus controlled adhesive-infiltrated demineralized dentin (AIDD).
• To evaluate the infiltration of resin monomers into dentin collagen fibrils under wet bonding conditions.

Main Methods:

• Human third molars were sectioned into adjacent fractions.
• One fraction underwent controlled demineralization and infiltration (AIDD) with Single Bond (SB) adhesive.
• The adjacent fraction was treated with SB using wet bonding.
• Sections were stained with Goldner's trichrome and analyzed using micro-Raman spectroscopy.

Main Results:

• Histomorphologic analysis revealed a porous collagen web at the a/d interface under wet bonding.
• Micro-Raman spectroscopy indicated primary infiltration by hydroxyethyl methacrylate (HEMA) in the wet bonding interface.
• AIDD showed a more optimized hybrid layer compared to the wet bonding interface.

Conclusions:

• Wet bonding results in a porous a/d interface with limited infiltration by resin monomers.
• The presence of hydrolytically unstable HEMA in the wet bonding interface may impact long-term bond stability.
• Controlled infiltration techniques yield superior interface quality compared to standard wet bonding procedures.