Penetration into dentin of sodium hypochlorite associated with acid solutions.
OBJECTIVE
The objective of this study was to evaluate the penetration of 2.5% NaOCl associated with 17.0% EDTA, 1.0% citric acid, and 1.0% peracetic acid into dentin tubules.


METHODS
The roots of 44 bovine incisors were cross-sectioned and 5-mm-long fragments were produced from their middle thirds. The specimens were instrumented with ProTaper hand files, stained in crystal violet, then sectioned mesiodistally. The buccal fragments were divided into 4 groups (n = 9) and subjected to 2 consecutive 10-minute immersion periods in one of the following acid solutions combined with 2.5% NaOCl: 17.0% EDTA (group 1), 1.0% citric acid (group 2), and 1.0% peracetic acid (group 3). Nine fragments were immersed in 2.5% NaOCl (group 4). The analysis of the penetration of NaOCl solutions into dentin was performed by measuring the depth of crystal violet stain that was bleached using a steromicroscope under ×50 magnification. Statistical comparisons were carried out by Kruskal-Wallis and Dunn's tests at the 5% significance level.


RESULTS
Group 1 showed less penetration into dentin than group 4 (P < .05). No statistically significant differences were observed among groups 2, 3, and 4 (P > .05).


CONCLUSIONS
Association of NaOCl with acid solutions did not increase its penetration depth into root dentin.
Araraquara Dental School, São Paulo State University, Araraquara, SP, Brazil.
Milton Carlos
MC
Kuga
Érica
É
Gouveia-Jorge
Mário
M
Tanomaru-Filho
Juliane Maria
JM
Guerreiro-Tanomaru
Idomeo
I
Bonetti-Filho
Gisele
G
Faria
D000818:Animals; D002417:Cattle; D019343:Citric Acid / Q000493:pharmacokinetics; D004396:Coloring Agents; D003786:Dental Pulp Cavity / Q000648:ultrastructure*; D003804:Dentin / Q000648:ultrastructure*; D004492:Edetic Acid / Q000493:pharmacokinetics; D005840:Gentian Violet; D008422:Materials Testing; D010463:Peracetic Acid / Q000493:pharmacokinetics; D011897:Random Allocation; D012388:Root Canal Irrigants / Q000493:pharmacokinetics*; D018915:Root Canal Preparation / Q000295:instrumentation; D012973:Sodium Hypochlorite / Q000493:pharmacokinetics*; D013696:Temperature; D013997:Time Factors
D004396:Coloring Agents; D012388:Root Canal Irrigants; D019343:Citric Acid; D004492:Edetic Acid; D012973:Sodium Hypochlorite; D010463:Peracetic Acid; D005840:Gentian Violet