Cavity wall adaptation of resin-based composites lined with flowable composites

Area of Science:

• Dental Materials Science
• Biomaterials Engineering

Background:

• Dental restorations require excellent adhesion to tooth structure to ensure longevity.
• Resin-based composites (RBCs) are widely used, with flowable and condensable types offering different handling properties.
• Understanding the marginal integrity of different RBC types is crucial for clinical success.

Purpose of the Study:

• To compare the marginal adhesion of a flowable resin-based composite (RBC) versus a condensable RBC to prepared tooth structure.
• To evaluate gap formation at the tooth/restoration interface using scanning electron microscopy (SEM).

Main Methods:

• Fifteen human teeth underwent Class I preparation.
• Teeth were divided into three groups, with restorations using either a flowable RBC or a condensable RBC with different bonding agents.
• Restored teeth were subjected to thermocycling, sectioning, and SEM evaluation for marginal gap formation.

Main Results:

• Scanning electron microscopy (SEM) revealed no marginal gaps at the tooth/restoration interface for the flowable RBC.
• Significant differences (P < 0.05) in wall adaptation were observed between the groups utilizing condensable RBC.
• The flowable RBC exhibited superior marginal adaptation compared to the condensable RBC in this study.

Conclusions:

• Flowable resin-based composites demonstrate excellent marginal adaptation to tooth structure.
• Condensable resin-based composites may present challenges with marginal integrity and wall adaptation.
• The choice of RBC and bonding system can significantly impact the formation of marginal gaps in dental restorations.