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Root Canal Preparation Does Not Induce Dentinal Microcracks In Vivo.
Angambakkam Rajasekaran PradeepKumar1, Hagay Shemesh2, Durvasulu Archana3
1Department of Conservative Dentistry and Endodontics, Thai Moogambigai Dental College and Hospital, Dr. M.G.R. Educational and Research Institute, Chennai, India.
Journal of Endodontics
|August 19, 2019
Summary
This in vivo study found that neither ProTaper rotary (PTR) nor ProTaper hand (PTH) instruments caused significant dentinal microcracks during root canal preparation. Micro-computed tomographic technology confirmed the absence of these cracks in premolars.
Area of Science:
- Endodontics
- Dental Materials Science
- Biomaterials
Background:
- Dentinal microcracks can compromise tooth integrity after endodontic procedures.
- Evaluating iatrogenic damage from root canal instrumentation is crucial for clinical success.
Purpose of the Study:
- To compare the incidence of dentinal microcracks following root canal preparation using ProTaper rotary (PTR) and ProTaper hand (PTH) systems.
- To assess the in vivo development of microcracks in premolars prepared with different instrumentation techniques.
Main Methods:
- Sixty premolars indicated for extraction were used in an in vivo study.
- Teeth were divided into positive/negative controls and experimental groups using PTR or PTH systems.
- Micro-computed tomographic technology was employed to analyze 43,361 cross-sectional root images for dentinal microcracks.
Main Results:
- Positive controls exhibited apical third microcracks; negative controls showed none.
- No microcracks were detected in the ProTaper rotary (PTR) group.
- A single specimen in the ProTaper hand (PTH) group showed minimal incomplete microcracks (0.66% of slices).
Conclusions:
- Root canal preparation with both PTR and PTH instruments did not induce significant dentinal microcracks in vivo.
- The findings suggest that these ProTaper systems are safe regarding the formation of dentinal microcracks.
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