Adsorption of 2-hydroxyethyl methacrylate on dentin from aqueous solution

Area of Science:

• Biomaterials Science
• Dental Materials
• Surface Chemistry

Background:

• Dentin bonding agents are crucial for dental restorations.
• Understanding the interaction between priming agents and dentin is essential for improving bond durability.
• 2-hydroxyethyl methacrylate (HEMA) is a common component in dental adhesives.

Purpose of the Study:

• To investigate the adsorption characteristics of 2-hydroxyethyl methacrylate (HEMA) on bovine dentin.
• To elucidate the priming effects of HEMA on dentin, particularly its role in demineralization resistance.
• To understand the infiltration mechanism of HEMA within the dentin structure.

Main Methods:

• Adsorption isotherms were studied to quantify HEMA uptake by dentin powder.
• Demineralization resistance was assessed using 6N HCl treatment after HEMA adsorption.
• Scanning Electron Microscopy (SEM) was employed to examine dentin surface morphology and layer formation.

Main Results:

• HEMA adsorption reached equilibrium slowly, with a linear isotherm and a plateau indicating significant uptake (approx. 2.5% by weight).
• HEMA-adsorbed dentin showed increased resistance to demineralization by 6N HCl after heating.
• SEM revealed a demineralization-resistant layer on HEMA-treated tooth sections, suggesting infiltration into intertubular dentin.

Conclusions:

• HEMA effectively adsorbs onto bovine dentin, forming a substantial layer.
• The adsorbed HEMA enhances dentin's resistance to acid demineralization, indicating a protective priming effect.
• HEMA infiltrates into the intertubular dentin, contributing to improved bonding and structural integrity.