A comparative scanning electron microscopy evaluation of smear layer removal with apple vinegar and sodium hypochlorite associated with EDTA.
OBJECTIVE
The purpose of this study was to evaluate by scanning electron microscopy (SEM) the removal of smear layer from the middle and apical root thirds after use of different irrigating solutions.


METHODS
Forty roots of permanent human teeth had their canals instrumented and were randomly assigned to 4 groups (n=10), according to the irrigating solution: apple vinegar (group A), apple vinegar finished with 17% ethylenediaminetetraacetic acid (EDTA) (group B), 1% sodium hypochlorite (NaOCl) finished with 17% EDTA (group C) and saline (group D - control). After chemomechanical preparation, the roots were cleaved longitudinally and their middle and apical thirds were examined by SEM at ×1,000 magnification. Two calibrated examiners (kappa=0.92) analyzed the SEM micrographs qualitatively attributing scores that indicated the efficacy of the solutions in removing the smear layer from the surface of the dentin tubules (1 - poor, 2 - good and 3 - excellent). Data from the control and experimental groups were analyzed by the Kruskal-Wallis and Dunn's test, while the Wilcoxon test was used to compare the middle and apical thirds of the canals within the same group (a=0.05).


RESULTS
The middle third presented less amount of smear layer than the apical third, regardless of the irrigant. There was statistically significant difference (p=0.0402) among the groups in the middle third. In the apical third, the apple vinegar/EDTA group showed the greatest removal of smear layer (p=0.0373).


CONCLUSIONS
Apple vinegar associated or not with EDTA was effective in removing smear layer when used as an endodontic irrigant.
University of São Paulo, São Paulo, Brazil.
George Táccio de Miranda
GT
Candeiro
Isabela Barbosa de
IB
Matos
Clarice Fernandes Eloy da
CF
Costa
Cristiane Sá Roriz
CS
Fonteles
Mônica Sampaio do
MS
Vale
D019342:Acetic Acid / Q000494:pharmacology; D000891:Anti-Infective Agents, Local / Q000494:pharmacology; D002614:Chelating Agents / Q000494:pharmacology; D003786:Dental Pulp Cavity / Q000187:drug effects; D003804:Dentin / Q000187:drug effects*; D004492:Edetic Acid / Q000494:pharmacology; D006801:Humans; D027845:Malus / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D011897:Random Allocation; D012388:Root Canal Irrigants / Q000494:pharmacology*; D016369:Smear Layer; D012973:Sodium Hypochlorite / Q000494:pharmacology; D018709:Statistics, Nonparametric
D000891:Anti-Infective Agents, Local; D002614:Chelating Agents; D012388:Root Canal Irrigants; D004492:Edetic Acid; D012973:Sodium Hypochlorite; D019342:Acetic Acid