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Voids and interlayer gaps in Class 1 posterior composite restorations: a comparison between a microlayer and a
Nachum Samet1, Kung-Rock Kwon, Phoebe Good
1Department of Restorative Dentistry and Biomaterials Sciences, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, USA. Nachum_samet@hsdm.harvard.edu
Quintessence International (Berlin, Germany : 1985)
|November 3, 2006
Summary
Microlayering resin composite restorations significantly reduces voids and interlayer gaps compared to the 2-layer technique. This technique improves the quality of dental restorations by minimizing internal defects.
Area of Science:
- Dental Materials Science
- Restorative Dentistry
- Biomaterials Engineering
Background:
- Dental composites are widely used for tooth restorations.
- Internal voids and gaps in composite restorations can compromise their longevity and performance.
- Understanding placement techniques is crucial for optimal restoration quality.
Purpose of the Study:
- To compare the presence of interlayer gaps between hybrid composites placed using a microlayer technique versus a 2-layer technique.
- To evaluate the impact of different composite placement strategies on internal restoration integrity.
Main Methods:
- Standardized Class 1 cavities were prepared in 40 extracted posterior teeth.
- Two resin composite placement techniques were compared: a 2-layer technique (10 teeth) and a microlayer technique (30 teeth).
- Scanning electron microscopy (SEM) was utilized to detect and analyze voids and interlayer gaps.
Main Results:
- Voids were prevalent (85-100%) within the bulk of resin composite materials in most samples.
- A statistically significant association between the 2-layer technique and the presence of bubbles was observed (P = .04).
- Irregular interlayer gaps were found in 5-15% of specimens, with no significant difference across study groups.
Conclusions:
- Voids are commonly found within bulk resin composite materials.
- The 2-layer technique showed a higher incidence of gaps compared to the microlayer technique.
- Employing a microlayering technique for resin composite placement may lead to a reduction in internal gaps, potentially enhancing restoration quality.
