Microleakage of Composite Resin Restorations with Dentin Margins

This study evaluated the effects of the pretreatment of the cavity on microleakage of the composite resin restorations with dentin margins. The labial surfaces of bovine teeth were ground until the dentin was exposed. Two standardized round cavities were prepared side by side. Four kinds of cleaning agents; 3% aluminum lactate, 10% ascorbic acid, 10% citric acid and 10% phosphoric acid were applied for 60 seconds to one of the two cavities. The other was left without cleaning. After bonding, a composite resin was inserted into cavity. The restored teeth were thermocycled, prior to immersion in dye for 24 hours.The dentin bonding agent singly could not prevent dye penetration at the cervical dentin margin, and prior to bonding the pretreatment of dentin with some cleaning agents was effective for decreasing microleakage.