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Published on: July 21, 2014
The effect of smear layer removal on marginal contraction gaps
Journal of Oral Rehabilitation
|July 1, 1994
Summary
Removing the smear layer with ethylenediamine tetra-acetic acid (EDTA) did not significantly improve dentine bonding agent effectiveness. Smaller marginal contraction gaps were observed, but the difference was not statistically significant for composite resin bonding.
Area of Science:
- Dental Materials Science
- Adhesive Dentistry
- Biomaterials
Background:
- The smear layer, a layer of debris on dentine surfaces, can impede the adhesion of dental restorative materials.
- Agents that remove the smear layer are hypothesized to enhance the bond strength between dentine and bonding agents.
- Understanding smear layer effects is crucial for improving the longevity of dental restorations.
Purpose of the Study:
- To investigate the impact of smear layer removal using ethylenediamine tetra-acetic acid (EDTA) on the efficacy of a specific dentine bonding agent.
- To evaluate the reduction in marginal contraction gaps in composite resin restorations after EDTA pretreatment.
- To determine if EDTA pretreatment significantly improves the bonding effectiveness of the tested agent.
Main Methods:
- Eighty dentine cavities were prepared and divided into two groups: control and experimental.
- The experimental group received pretreatment with 0.5% ethylenediamine tetra-acetic acid (EDTA) for 60 seconds.
- Both groups were restored with Prisma Universal Bond 2 Adhesive and Prisma Fil Resin, followed by thermocycling and measurement of marginal contraction gaps.
Main Results:
- The experimental group (EDTA treated) showed a mean marginal contraction gap of 0.021%, compared to 0.027% in the control group.
- While the EDTA-treated group exhibited smaller gaps, this difference was not statistically significant.
- No infiltration of restorative material into the dentine tubules was observed in either group.
Conclusions:
- Pretreatment with 0.5% EDTA did not yield a statistically significant improvement in reducing marginal contraction gaps for the tested dentine bonding agent.
- The findings suggest that while smear layer removal might influence gap formation, its effect on this specific bonding system's performance was marginal.
- Further research may be needed to explore alternative smear layer removal techniques or different bonding agents for enhanced dentine adhesion.
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