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 .
The effect of etching on bacterial microleakage of an adhesive composite restoration.
OBJECTIVES The incidence of bacterial microleakage , pulp inflammation and necrosis associated with dentine etching treatments prior to restoration are not known . Consequently , to resolve some of the controversy surrounding the effects and importance of vital dentine etching , the authors investigated these factors . METHODS 110 st and ardised class V cavities were cut into buccal dentine , without exposing the pulp of teeth scheduled for extraction for orthodontic reasons . Cavities were either left unetched , or etched with the non-equivalent treatments of phosphoric acid gel for 60s or Ethylenediaminetetraacetic acid ( EDTA ) for 30s , prior to placement of composite resin . Teeth were collected and pulp responses were evaluated according to ISO guidelines , using pathohistomorphometric analysis and ANOVA statistics . RESULTS Etching was found to be correlated to bacterial microleakage ( p=0.0001 ) and tertiary dentine formation ( p=0.0023 ) . Bacterial microleakage was correlated to inflammatory activity ( p=0.0001 ) . The frequency of bacterial microleakage was : no etching ( 65 % ) , EDTA ( 51 % ) and phosphoric acid ( PA ) ( 20 % ) . SIGNIFICANCE Vital dentine etching treatment is of extreme importance for the placement of RC to minimise bacterial microleakage .  PA etching proved to be more effective at preventing bacterial microleakage than non-etching , and etching with EDTA
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 .