الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 124 |  |  |
| | | from | 124 | | |
Abstract
Summary
This study was conducted to:
1. Assess and compare the effectiveness of final needle irrigation (FNI),
sonic activation using the EDDY tip and passive ultrasonic irrigation
(PUI) using Irrisafe tip regarding debris removal from the root canal
and isthmus area.
2. Evaluate the efficacy of adding surfactants to NaOCl on the cleanliness
of the root canal and isthmus.
Methods: Sixty mesial roots of mandibular first molars were used in this study.
After sectioning, pre-instrumentation images were taken using a digital
camera attached to a stereomicroscope (I0). Then, roots were equally divided
into two equal groups of 30 teeth according to the irrigant used as following:
group A1: 5.25% NaOCl
group A2: 5.25% Chlor-Xtra
During instrumentation, roots were reassembled in a custom-made copper
cube. After complete root canal instrumentation, the sections were removed from
the cube, and images were taken by a digital camera attached to a
stereomicroscope at the 30x magnification. After obtaining the postinstrumentation images (I1), thirty samples in each irrigant group 3 subgroups
according to the activation method as following:
Sub-group B0: FNI
Sub-group B1: Irrisafe activation
Sub-group B2: EDDY activation
After final irrigation, sections were removed from the block and images
were taken (I2). Images (I1, I2) were analyzed using ImageJ software to calculate
the total surface area of debris in the root canals and the isthmus after both
instrumentation and final irrigation protocol. The outline of the root canals and
the isthmus were traced as well as the area occupied by debris within the canals
Summary
81
and within the isthmus. These areas were quantified by counting the number of
pixels. Then the clean area free of debris was calculated by subtracting the area
occupied by debris from the total area. The canal and isthmus cleanliness
percentage were calculated by dividing the area free of debris by the total area of
the root canal or isthmus to yield a percentage. The cleanliness difference before
and after final irrigation was calculated by subtracting cleanliness percentage
before final irrigation from cleanliness percentage after final irrigation.
Results: In both irrigants’ groups, all three final irrigation protocols resulted in
significant improvement in isthmus and canal cleanliness compared to the
cleanliness after the completing the preparation.
Regarding the comparison of mean % of isthmus cleanliness between
different levels (2, 4 and 6 mm) within the same subgroup, FNI showed the most
improvement in removing residual debris in the 2 mm level compared to 4 and 6
mm. While in the PUI group, the improvement in the 2 mm level was the least
significant compared to the two other levels. However, using EDDY did not result
in a difference between levels. As for the comparison between the activation
techniques regarding isthmus cleanliness, FNI had the least improvement in
isthmus cleanliness at all levels. The cleaning efficiency results in the 2 mm level
revealed significantly superior improvement in isthmus cleanliness by EDDY
compared to PUI. In the 4 mm and 6 mm levels, when both activation techniques
are compared head to head, there was no significant difference between them in
improving isthmus cleanliness.
Concerning canal cleanliness, the difference in canal cleanliness
comparing the three levels within the same subgroup was insignificant when FNI
and PUI were used. While the improvement shown from using EDDY activation
was more significant in the 2 mm level compared to the 4 mm and 6 mm levels.
As for the comparison between the activation techniques regarding canal
cleanliness, FNI had a significantly lower effect on canal cleanliness
improvement than both activation techniques. On the other hand, the difference
Summary
82
between both activation techniques was insignificant. At both the 4 mm and 6
mm levels in both irrigant groups, there was no significant difference between all
three techniques.
Also, there was no significant difference between NaOCl and Chlor-Xtra
regarding their cleaning efficiency in both root canals and isthmuses whether they
were activated or not