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Influence of elasticity on gap formation in a lining technique with flowable composite
Eitetsu Cho1, Hirokazu Chikawa, Ryuzo Kishikawa
1Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University, Japan. cho.ope@tmd.ac.jp
Dental Materials Journal
|November 2, 2006
Summary
Flowable composites used as liners in direct composite restorations prevent gaps at the base. Higher elastic modulus flowable composites effectively reduce gaps between restorative materials.
Area of Science:
- Dental Materials Science
- Biomaterials Engineering
Background:
- Direct composite restorations are widely used in dentistry.
- Minimizing interfacial gaps is crucial for restoration longevity and preventing secondary caries.
- Flowable composites are often used as liners, but their interaction with condensable composites requires investigation.
Purpose of the Study:
- To evaluate the efficacy of flowable composites as liners in direct composite restorations.
- To determine the influence of elastic moduli of flowable and condensable composites on interfacial gap formation.
Main Methods:
- A 1 mm-thick layer of flowable composite was applied to a treated cavity mold and irradiated.
- The remaining cavity was filled with a condensable composite and irradiated.
- Interfacial gap formation was assessed at two interfaces: cavity floor-flowable composite and flowable-condensable composite.
Main Results:
- No gaps were observed at the interface between the cavity floor and the flowable composite liner.
- The percentage of gap formation between the flowable and condensable composites was directly related to the difference in their elastic moduli.
- Flowable composites with a higher elastic modulus demonstrated a reduction in gap formation.
Conclusions:
- Flowable composites serve as effective liners, preventing gaps at the base of direct composite restorations.
- The elastic modulus of the flowable composite liner is a critical factor in minimizing interfacial gaps between it and the overlying condensable composite.
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