Composite wall-to-wall polymerization contraction in dentin cavities treated with various bonding agents

Area of Science:

• Dental Materials Science
• Biomaterials Research
• Composite Restorations

Background:

• Extracted human teeth are crucial for dental composite bonding research.
• The influence of tooth storage conditions on experimental outcomes remains unclear.
• Standardized storage protocols are needed to ensure reliable and reproducible research findings.

Purpose of the Study:

• To evaluate the effect of various storage media on polymerization contraction of light-cured composites bonded to dentin.
• To determine if storage conditions influence the formation of contraction gaps in prepared dentin cavities.
• To assess the reliability of using stored human teeth in dental bonding studies.

Main Methods:

• Cylindrical dentin cavities were prepared in extracted human teeth.
• Light-cured composite material was applied with or without five different dentin bonding agents.
• Teeth were stored for up to 4 weeks in tap water, 1.0% chloramine, 0.1% benzalkonium chloride, or 0.9% sodium chloride solutions.
• Wall-to-wall polymerization contraction and contraction gap width were measured.

Main Results:

• Storage in tap water or 1.0% chloramine solution showed no significant effect on contraction gap width.
• Storage in 0.1% benzalkonium chloride or 0.9% sodium chloride solutions occasionally resulted in altered contraction gap sizes.
• Results indicate variability in the impact of different storage media on composite-to-dentin bonding outcomes.

Conclusions:

• Tap water and 1.0% chloramine are suitable storage media for extracted teeth used in polymerization contraction studies.
• Certain storage solutions, such as benzalkonium chloride and sodium chloride, can interfere with contraction gap measurements.
• Careful consideration of storage conditions is essential for accurate and reproducible research on dental composite bonding.