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Microleakage in class II restorations: open vs closed centripetal build-up technique
Andrea Fabianelli1, Alessandro Sgarra, Cecilia Goracci
1University of Sheffield, Adult Dental Care, School of Clinical Dentistry, Sheffield, United Kingdom. a.pollington@sheffield.ac.uk
Operative Dentistry
|June 11, 2010
Summary
The open-sandwich technique for Class II resin composite restorations showed significantly less microleakage compared to the closed-sandwich technique. However, neither method completely prevented microleakage at the cervical margin.
Area of Science:
- Restorative Dentistry
- Dental Materials Science
Background:
- Microleakage in Class II restorations is a significant clinical concern.
- The centripetal build-up technique aims to improve adaptation, but the optimal placement of flowable resin composite remains debated.
Purpose of the Study:
- To compare microleakage in Class II restorations using the open-sandwich versus closed-sandwich technique with flowable resin composite.
- To evaluate the effect of flowable composite placement relative to interproximal wall construction.
Main Methods:
- Thirty molars underwent Class II preparations with margins below the cementum-enamel junction.
- Group 1 (open-sandwich): Flowable composite base exposed at margin. Group 2 (closed-sandwich): Hybrid composite interproximal wall first, then flowable composite.
- Restorations subjected to 500 thermal cycles; dye penetration and SEM evaluated marginal adaptation.
Main Results:
- The open-sandwich technique demonstrated significantly lower dye penetration (p < 0.001).
- Flowable composite under hybrid composite (Group 1) showed better marginal adaptation and fewer voids.
- Complete prevention of microleakage was not achieved in either group.
Conclusions:
- The open-sandwich technique offers superior marginal adaptation and reduced microleakage in Class II resin composite restorations.
- While improved, neither technique fully eliminated microleakage, indicating a need for further refinement.
- Placement of flowable resin composite as a base layer beneath hybrid composites enhances restoration quality.
