Microleakage of a condensable resin composite: An in vitro investigation

Objective: The purpose of this investigation was to evaluate microleakage i n Class II cavities restored with the condensable resin composite SureFil, placed with or without a liner and 1 of 2 different dentin bonding agents. Method and materials: Extracted noncarious human teeth were randomly divide d into 4 groups of 15 each and restored according to manufacturer's instruc tions: group 1, SureFil and Prime a Bond NT; group 2, SureFil and PQ1;group 3, SureFil, PermaFlow, and PQ1;group 4, Heliomolar and Syntac Single-Compo nent (control). Specimens were stored in 37 degrees C water for 24 hours. A ll specimens were thermocycled between 5 degrees C and 55 degrees C for 500 cycles. Each specimen was immersed in 0.2% basic fuchsin dye for 24 hours and then sectioned longitudinally and horizontally. Dye penetration at enam el and cementum margins were viewed at x30 magnification by 2 independent, calibrated evaluators. Specimens exhibiting dye penetration greater than or equal to 0.1 mm beyond the cavosurface margin were considered to have leak age. Results: Chi-square tests revealed no statistically significant differ ences in the presence of microleakage when all groups were analyzed togethe r. However, 2 by 2 comparisons revealed that group 3 had significantly fewe r specimens with microleakage than did groups 1, 2, or 4. Conclusion: To li mit microleakage, a flowable composite should be used as a liner when a con densable composite material is used.