الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 236 |  |  |
| | | from | 236 | | |
Abstract
Abstract
Keywords: Centering ability, Cleaning Efficiency, OneShape, ProTaper
Universal, WaveOne.
Aim: To evaluate centering ability, amount of removed dentin and cleaning
efficacy of hand NiTi Flex K-files, ProTaper Universal system, OneShape
and WaveOne system in curved root canals. Materials and Methods: Forty
extracted human premolars with a range of canal curvature (21º-39º) were
used. Samples were randomly divided into four groups (n=10). group I
(control group NiTi-Flex), group II (ProTaper), group III (OneShape) and
group IV (WaveOne Primary). Standardized pre- and post-instrumentation
Cone Beam Computed Tomography (CBCT) images were recorded at three
root canal levels (3, 6, and 9 mm from the apex) and superimposed.
Centering ability of each instrument was evaluated and amount of removed
dentin was calculated by differences between pre-and post-instrumentation
canal volumes. Roots were splitted longitudinally and superficial debris and
smear layer were separately evaluated at apical, middle and coronal levels.
Results: WaveOne system showed the highest centering ratios at all tested
canal levels in both directions. Apical thirds of all groups showed the highest
centering ratios while the coronal showed the lowest. ProTaper system group
recorded significantly highest amount of root dentin removal compared to
other groups. WaveOne system exhibited significantly less amount of
remaining debris compared to ProTaper and hand NiTi Flex files. Apical
canal levels possess the highest amount of debris while the least amount was
recorded coronally. No significant differences in smear layer scores were
found among tested groups at all root levels. Conclusions: Reciprocating
WaveOne files had more centering ability and cleaning efficacy than other
tested instruments. ProTaper Universal system removed significantly high
amount of dentin in comparison to other systems.