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Vertical force and torque analysis during mechanical preparation of extracted teeth using hand ProTaper instruments
Snježana Glavičić1, Ivica Anić, Alen Braut
1Department of Dental Pathology, School of Dentistry, Medical Faculty, University of Rijeka, Rijeka, Croatia. snjezana_glavicic@yahoo.com
Summary
Hand ProTaper instrumentation generates higher vertical force and torque in narrower root canals. Increased contact surface area amplifies these forces in both wider and narrower canals.
Area of Science:
- Endodontics
- Dental instrument mechanics
Background:
- Root canal instrumentation aims to clean and shape the root canal system.
- Understanding the forces and torques involved is crucial for optimizing instrumentation techniques and preventing procedural errors.
Purpose of the Study:
- To measure and analyze the vertical force and torque during hand ProTaper instrumentation in wider and narrower root canals.
- To compare the biomechanical forces exerted in different root canal diameters.
Main Methods:
- Twenty human incisors were divided into two groups representing wider (upper incisors) and narrower (lower incisors) root canals.
- A custom-built device was used to measure vertical force and torque during hand ProTaper instrumentation.
- Statistical analysis was performed using the Mann-Whitney U-test (P<0.05).
Main Results:
- Vertical force ranged from 0.25-2.58 N in wider canals and 0.38-6.94 N in narrower canals.
- Torque ranged from 0.53-12.03 Nmm in wider canals and 0.94-10.0 Nmm in narrower canals.
- Both vertical force and torque were significantly higher in narrower root canals compared to wider ones.
Conclusions:
- Hand ProTaper instrumentation generates greater vertical force and torque in root canals with smaller diameters.
- An increased contact surface area during instrumentation leads to higher vertical force and torque, irrespective of canal width.
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