الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 160 |  |  |
| | | from | 160 | | |
Abstract
This study assessed the occurrence of micro-cracks during retrograde root canal cavity preparation by comparing the use of Hyflex EDM with AS9D retrotips utilizing a stereomicroscope.
A total of thirty-six maxillary anterior teeth were included in the study. After performing root end resection, the teeth were divided into three groups randomly (n=12). The allocation was based on the system used;
group I: Hyflex EDM.
group II: AS9D retrotip.
group III: Control group.
Following retrograde preparation performed under the operating dental microscope, the specimens were horizontally sectioned using a microtome precision cut-off machine at (3 mm, 6 mm, and 9 mm) from the apex. The presence of dentinal cracks was then examined using a stereomicroscope. The microcracks observed were recorded based on their number, type, and location. Statistical analysis was conducted using the Pearson Chi Square test with Monte Carlo simulation to determine the significance of the findings. The predetermined significance level was set at p < 0.05. Data was analysed using IBM SPSS version 23.
The results demonstrated a statistically significant difference in the total number of cracks among the three groups (≤0.010). The controlled memory files group had a low number of cracks, while the ultrasonic group had the highest number of cracks. The control group had the least number of cracks overall. However, there was no significant difference among the groups in terms of the section level, type, and location of the cracks.