Under the conditions of these in vitro leakage studies , it is concluded that smear layer removal improves the fluid-tight seal of the root canal system whereas other factors such as the obturation technique or the sealer , did not produce significant effects
The purpose of this systematic review was to determine whether smear layer removal reduces leakage of obturated human teeth in vitro .
Role of hybridization on marginal leakage and bond strength.
PURPOSE To evaluate whether the hybrid layer significantly contributes to the seal of adhesive Class V restorations placed in vivo and to the bond strength obtained in vitro . MATERIAL S AND METHODS 20 periodontally severely compromised anterior teeth were selected for the leakage study . In each tooth , one round 3 mm wide V-shaped cavity with a maximum depth of 2 mm was prepared on the labial surface crossing the cementum-enamel junction . The sample teeth were r and omly divided into two groups of ten sample s each : in Group 1 , Scotchbond Multi- Purpose Plus was applied in combination with Z-100 following the manufacturer 's instructions . In Group 2 the bonding procedure was the same as in Group 1 , except that after the phosphoric acid treatment , the cavities were treated with 5 % NaOCl for 2 min . Following a period of clinical service of 60 - 90 days , the teeth were extracted and processed for the leakage test . RESULTS At the enamel site , 30 % of the sample s of Group 1 and 70 % of the sample s of Group 2 showed dye penetration . At the dentin site , 50 % of the sample s of Group 1 showed leakage , while all the sample s of Group 2 were severely infiltrated . Statistically significant differences between the groups both for the enamel sites ( P < 0.05 ) and for dentin-cementum sites ( P < 0.001 ) were found . Bond strength tests were performed on 2 mm thick dentin slides of tapered Class I cavities ( n = 10 in each group ) . The mean bond strength value obtained from cavities treated without NaOCl was 15.23 ( + /-1.40 ) MPa and with NaOCl treatment 20.52 ( + /-1.70 ) MPa . Statistical analysis showed significant differences ( P < 0.05 ) between the two groups . No hybrid layer was detected on the NaOCl-treated sample s by scanning electron microscopy
Under the conditions of these in vitro leakage studies , it is concluded that smear layer removal improves the fluid-tight seal of the root canal system whereas other factors such as the obturation technique or the sealer , did not produce significant effects
The purpose of this systematic review was to determine whether smear layer removal reduces leakage of obturated human teeth in vitro .