Effect of the cavity configuration factor on the marginal microleakage of esthetic restorative materials

To evaluate the effect of the cavity configuration factor (CF) on the marginal microleakage of cervical restorations with four aesthetic restorative materials.

Conventional cavities, 2.9 mm in diameter and 1.5 mm deep, with CF=2.7 and "saucer"-shaped ones with CF=2 were created in 60 extracted premolars. The following groups were established: G1: Z100/Single Bond, G2: Freedom/Stae, G3: Vitremer/Primer and G4: Durafill/Durafill Bond, following each manufacturer's directions. Thermocycling of the specimens was performed in an aqueous solution of 2% buffered methylene blue, with the temperature varying between 5 to 55 degrees C, for a total of cycles of 60 minutes per day, for 7 days. The specimens were then sectioned and evaluated by two observers using photographs acquired from a stereomicroscope. The values were subjected to Kruskal-Wallis analysis and the Dunn and Wilcoxon test.

The averages of the microleakage scores observed in the conventional and "saucer"-shaped cavities were respectively: G1: 0.66/0.46; G2: 0.92/0.69; G3: 1.8/1.86; G4: 3.54/2.3.