Abstract
Objectives: Dentin bonds made with one-bottle etch-and-rinse and self-etch adhesives are affected by the formation of interfacial blisters, porosities and deterioration. The first objective of this study was to evaluate the fluid flow through resin-dentin interfaces created by self-etching adhesives applied to deep dentin using a replica technique and by directly measuring dentin permeability (P). The second objective was to examine the effect of intrapulpal pressure on the microtensile bond strength of these adhesives. Methods: A fluid-transport model was used to measure the fluid permeability (%P) through different adhesives. Impressions of bonded dentin were taken with a polyvinylsiloxane impression material to monitor fluid transudation from the surface of the adhesive. Positive replicas were fabricated for SEM examination. Two groups of resin-bonded specimens (pulpal pressure versus no pulpal pressure) were created for microtensile bond strength evaluation. Adhesive application was performed under 0 cm H2O. Pulpal pressure group was submitted to 20 cm H2O of pulpal pressure during build-up procedures. Results: Clearfil Protect Bond exhibited the lowest permeability and fewest numbers of fluid droplets over the surface of the bonded dentin. G-Bond and Clearfil-S3 Bond were more permeable than Clearfil Protect Bond. One Up Bond F was the most permeable adhesive. A highly significant correlation was observed between the relative permeability of these adhesives (%P) and the number of fluid droplets on the adhesive surfaces. The application of pulpal pressure significantly reduced bond strength. Significance: Resin-dentin bonds created by contemporary self-etch adhesives are susceptible to fluid permeation induced by pulpal pressure. HEMA-based adhesives showed the largest reductions in bond strengths after pulpal pressure application.
Original language | English (US) |
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Pages (from-to) | 705-713 |
Number of pages | 9 |
Journal | Dental Materials |
Volume | 23 |
Issue number | 6 |
DOIs | |
State | Published - Jun 2007 |
Keywords
- Dentin bonding systems
- Hybrid layer
- Hydrophilic polymers
- Microtensile bond strength
- Permeability
- SEM
- Water droplets
- Water uptake
ASJC Scopus subject areas
- General Materials Science
- General Dentistry
- Mechanics of Materials