Rohit Kansal1, Akhil Rajput2, Sangeeta Talwar1, Ruchika Roongta1, Mahesh Verma3. 1. Department of Conservative Dentistry and Endodontics, Maulana Azad Institute of Dental Sciences, New Delhi, India. 2. Department of Conservative Dentistry and Endodontics, Maulana Azad Institute of Dental Sciences, New Delhi, India. Electronic address: akhilraj_24@yahoo.com. 3. Maulana Azad Institute of Dental Sciences, New Delhi, India.
Abstract
INTRODUCTION: The role of motion kinematics in creating dentinal damage during instrumentation is not very clear. The purpose of this study was to compare the formation of dentinal cracks with instruments working in continuous rotation and reciprocating motion. METHODS: One hundred twenty extracted human mandibular premolars were selected for the study. Thirty teeth served as controls, and the remaining 90 teeth were divided into 3 groups depending on the root canal preparation technique. Group 1 samples were treated with WaveOne primary files (Dentsply Maillefer, Ballaigues, Switzerland), group 2 samples with single F2 ProTaper (Dentsply Maillefer) working in reciprocating motion, and group 3 samples were prepared with sequential ProTaper (Dentsply Maillefer) until F2 working in continuous rotation motion. Roots were then sectioned at 3, 6, and 9 mm from the apex, and the cut surface was observed under a stereomicroscope for the presence of dentinal microcracks. RESULTS: The control group and WaveOne, single F2 ProTaper in reciprocating motion, and continuous ProTaper groups caused cracks in 0%, 15%, 26%, and 53% of samples, respectively. A statistically significant difference was found between 2 reciprocating file groups (WaveOne and single F2 ProTaper in reciprocating motion) and the continuous rotation group (ProTaper) (P < .05). However, no significant difference was found among the 2 reciprocating file groups (P > .05). CONCLUSIONS: Dentinal cracks are produced irrespective of motion kinematics. Within the limits of this study and the current literature, such incidence is less with instruments working in reciprocating motion compared with those working in continuous rotation.
INTRODUCTION: The role of motion kinematics in creating dentinal damage during instrumentation is not very clear. The purpose of this study was to compare the formation of dentinal cracks with instruments working in continuous rotation and reciprocating motion. METHODS: One hundred twenty extracted human mandibular premolars were selected for the study. Thirty teeth served as controls, and the remaining 90 teeth were divided into 3 groups depending on the root canal preparation technique. Group 1 samples were treated with WaveOne primary files (Dentsply Maillefer, Ballaigues, Switzerland), group 2 samples with single F2 ProTaper (Dentsply Maillefer) working in reciprocating motion, and group 3 samples were prepared with sequential ProTaper (Dentsply Maillefer) until F2 working in continuous rotation motion. Roots were then sectioned at 3, 6, and 9 mm from the apex, and the cut surface was observed under a stereomicroscope for the presence of dentinal microcracks. RESULTS: The control group and WaveOne, single F2 ProTaper in reciprocating motion, and continuous ProTaper groups caused cracks in 0%, 15%, 26%, and 53% of samples, respectively. A statistically significant difference was found between 2 reciprocating file groups (WaveOne and single F2 ProTaper in reciprocating motion) and the continuous rotation group (ProTaper) (P < .05). However, no significant difference was found among the 2 reciprocating file groups (P > .05). CONCLUSIONS: Dentinal cracks are produced irrespective of motion kinematics. Within the limits of this study and the current literature, such incidence is less with instruments working in reciprocating motion compared with those working in continuous rotation.
Authors: Giuseppe Troiano; Mario Dioguardi; Armando Cocco; Giovanni Giannatempo; Luigi Laino; Domenico Ciavarella; Elio Berutti; Lorenzo Lo Muzio Journal: Open Dent J Date: 2016-10-07