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Effect of Root Canal Preparation Techniques on Crack Formation in Root Dentin
Yazdan Shantiaee1, Omid Dianat2, Golnaz Mosayebi3
1Endodontic Department, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Iranian Center For Endodontic Research, Research Institute of Dental Sciences, Dental School, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Journal of Endodontics
|March 5, 2019
Summary
Single-file systems, whether rotary or reciprocating, significantly increase root crack formation in the apical third compared to manual files. Careful assessment of instrumentation techniques is crucial for preventing dentinal defects during root canal procedures.
Area of Science:
- Endodontics
- Dental Materials Science
Background:
- Root canal instrumentation can lead to dentinal defects, commonly known as cracks.
- Assessing the frequency of these cracks is vital for understanding procedural risks.
Purpose of the Study:
- To evaluate and compare the incidence of root crack formation using manual files, two rotary systems, and one reciprocating system.
- To identify which instrumentation techniques pose a higher risk for creating dentinal defects.
Main Methods:
- 150 mandibular premolars were divided into five groups: control (no intervention), hand files, ProTaper Universal rotary, OneShape rotary, and WaveOne reciprocating.
- Roots were sectioned at 3, 6, and 9 mm from the apex after preparation.
- Cracks were identified using light-emitting diode transillumination and stereomicroscope examination at ×40 magnification.
Main Results:
- A significant difference in crack frequency was observed among the groups (P < .05).
- Single-file systems (rotary and reciprocating) showed significantly higher crack incidence than manual files and control groups.
- The apical third (3 mm from apex) exhibited significantly more cracks with single-file systems (groups 4 and 5).
Conclusions:
- Rotary instrumentation can contribute to dentinal defects.
- Single-file systems, irrespective of motion (rotary or reciprocating), are associated with increased crack formation, particularly in the apical third of root canals.
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