Abstract
An In vitro study was carried out to compare the effects of the Smear layer and the pretreatment of the foot canal wall with tubular occluding desensitizing agent (6% ferric-oxalate) or a bonding agent on the coronal seal of endodontically treated teeth.
Seventy freshly extracted human teeth with single and straight canals were used in This study. The teeth were divided into five experimental groups: twelve teeth each, withone positive and one negative control for each. Group I: With intact smear layer, Group II: Without smear layer. Group III: With intact smear layer and with ferric-oxalate painting of the canal walls. Group IV: Without smear layer and with ferric-oxalate painting of the canal walls. Group V: Without smear layer and with bonding agent.
After canal obturation the access cavities were exposed to natural saliva then Pelikan ink. Teeth were cleared and linear dye penetration measured. The results showed that the removal of the smear layer significantly increased the tightness of the coronal seal, and pretreatment of the canal walls with ferric-oxalate significantly decreased the coronal microleakage more than with or without smear layer. Using the bonding agent with a hydrophilic primer, after removing the smear layer, showed significantly less microleakage than all other groups.
