Morphological Changes of Radicular Dentin After Exposure to Chelating Agents
Abstract:
Aim: The purpose of this study was to observe the effect of Q mix root canal irrigant compared to Ethylenediaminetetraacetic acid (EDTA) on radicular dentine with different contact times.
Materials and Methods: Ninety single-rooted human teeth were decoronated and instrumented to size 40/taper 0.06. the specimens were randomly allocated to 3 groups. In the control group (n=20), canals were irrigated with 3ml distilled water. In group 2 (n= 40), canals were irrigated with 3ml of 17% EDTA+ NaOCl, and further subdivided into group 2A (n=20) with a contact time of the 60s, and group 2B (n= 20) with a contact time of 90s. In group 3 (n=40), canals were irrigated with 3ml Q mix+ NaOCl, and subdivided into; Group 3A (n=20) with the 60s and 90s contact time respectively. After irrigation, the canals were rinsed with 5 mL saline. The coronal orifice and apical foramen were sealed, and the roots were split into two halves. The coronal, middle and apical parts were examined with a Scanning Electron Microscope (SEM) at 3000x magnification to evaluate the smear layer. Two-way ANOVA was used for analysis with statistical significance set at 0.05.
Results: EDTA + NaOCl with a 90 seconds exposure time was found to be more efficient in removing the smear layer in comparison to both EDTA + NaOCl with at 60 seconds exposure time and Qmix + 5.25% NaOCl with at 90 seconds irrigation in both cervical and middle one-third root regions. The interactive effect of irrigation regimens and radicular dentine area were not found to be significant.
Conclusion: Both irrigation methods were equally efficient in eliminating the smear layer with different contact time. However, SEM revealed that the combination of EDTA+ NaOCl with a 90 seconds contact time had more erosion effect on the dentinal wall.
