Chemical and ultramorphologic effects of ethylenediaminetetraacetic acid and sodium hypochlorite in young and old root canal dentin.

By Ozdemir HO, Buzoglu HD, Calt S, Cehreli ZC, Varol E, Temel A. 

Date: 08/2012
Journal: JOE


Purpose:  to evaluate & compare the time-dependent chemical and ultramorphologic effects of (EDTA) and (NaOCl) in young and old dentin

N= 64 extracted teeth


•Teeth were collected from young (<30 years) and old (>60 years) patients. •In 48 teeth, the dentin was reduced to a powder state and treated with EDTA or EDTA + NaOCl for 1 and 10 minutes, respectively.

•X-ray diffraction analysis was used to determine the changes in the composition of dentin through dissolution of hydroxyapatite (HAp).

•In the remaining teeth (n = 16), the root canals were prepared, bisected, and subjected to the same time-dependent treatment regimens.

•The changes in the number and area of dentinal tubules were calculated by image analysis.

Most highlighted Results:


Clinical significance:

In young root dentin – 10-minute treatment with EDTA + NaOCl does not significantly alter the chemical & ultramorphologic structure and thus appears to be unnecessary.

In old dentin – extended treatment time with EDTA + NaOCl should be avoided owing to excessive demineralization and erosion.

In both types of dentin, EDTA was not effective in complete removal of the smear layer