Bonding Performance and Interfacial Ultra-Morphology/Nanoleakage of a Modern Self-Curing Bulk-Fill Restorative...

Area of Science:

• Dental Materials Science
• Restorative Dentistry
• Biomaterials

Background:

• Evaluating novel self-curing restorative systems is crucial for improving clinical outcomes.
• Understanding the bonding performance and interfacial integrity of restorative materials is essential for long-term restoration success.

Purpose of the Study:

• To compare the bonding performance and interfacial ultramorphology of a new self-curing restorative system (STELA) against a conventional light-curing resin composite (CERAM).
• To assess the influence of etch-and-rinse (ER) and self-etch (SE) bonding modes on the restorative systems' performance on dentin.

Main Methods:

• Class I cavities in dentin were restored with CERAM/Prime & Bond Universal or STELA/adhesive primer.
• Specimens were subjected to microtensile bond strength testing, failure mode analysis, and scanning electron microscopy.
• Interfacial ultramorphology and nanoleakage were evaluated using dye-assisted confocal microscopy.

Main Results:

• Etch-and-rinse (ER) groups exhibited significantly higher bond strength than self-etch (SE) groups for both materials.
• STELA in SE mode showed significantly better bond strength than CERAM in SE mode.
• Nanoleakage was more prevalent in CERAM groups, while STELA groups showed better interfacial adaptation.

Conclusions:

• The self-curing STELA system offers a promising alternative for restoring deep class I cavities, providing adequate interfacial adaptation and strong dentin bonding.
• Conventional adhesives used with light-curing composites in deep cavities may lead to interfacial gaps and leakage.