The effectiveness of ethylenediaminetetraacetic, etidronic, and peracetic acids activated with ultrasonics or diode laser on calcium hydroxide removal from root canal walls.

Background: To assess the efficiency of ethylenediaminetetraacetic acid (EDTA), etidronic (HEBP), and peracetic (PAA) acids agitated with ultrasonic energy or diode laser on removing calcium hydroxide (CH) dressings from root canal walls.

Material And Methods: Single root canals of eighty extracted human teeth were chemomechanically instrumented and filled with CH. Sixty teeth were divided into six experimental groups (n = 10) according to the applied irrigation regimens for the removal of CH: Group 1: 5.25% NaOCl-17% EDTA, Passive ultrasonic irrigation (PUI); Group 2: 5.25% NaOCl + 9% HEBP, PUI; Group 3: 5.25% NaOCl-2% PAA, PUI; Group 4: 5.25% NaOCl-17% EDTA, Diode laser-activated irrigation (LAI); Group 5: 5.25% NaOCl + 9% HEBP, LAI; Group 6: 5.25% NaOCl-2% PAA, LAI. The other 20 teeth were served as negative (n = 10) and positive controls (n = 10). The residuary amount of CH was scored in coronal, middle, and apical thirds of the root canals by using scanning electron microscope. The data were statistically analyzed using Kruskal-Wallis H with Bonferroni adjusted Mann-Whitney U test with a significance level of 0.05.

Results: Etidronic acid activated with ultrasonics or diode laser removed the highest amount of CH from the middle third of root canals, compared to the other irrigation regimens (P < 0.001). Although the residual CH scores of PAA-PUI, PAA-LAI, and EDTA-PUI, EDTA-LAI groups were not statistically different from each other (P > 0.05), lower amount of CH was observed in the PAA-PUI and PAA-LAI groups.

Conclusions: Use of etidronic acid activated with ultrasonics or diode laser can be an appropriate irrigation regimen for CH removal from root canal system.