Joo-Yeong Lee1, Sang Won Kwak1, Jung-Hong Ha2, Ibrahim H Abu-Tahun3, Hyeon-Cheol Kim4. 1. Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Pusan National University, Yangsan, Korea. 2. Department of Conservative Dentistry, School of Dentistry, Kyungpook National University, Daegu, Korea. 3. Department of Conservative Dentistry, School of Dentistry, The University of Jordan, Amman, Jordan. 4. Department of Conservative Dentistry, School of Dentistry, Dental Research Institute, Pusan National University, Yangsan, Korea. Electronic address: golddent@pusan.ac.kr.
Abstract
INTRODUCTION: The aim of this study was to compare the cyclic fatigue, torsional resistance, and bending stiffness of single-file glide path preparation nickel-titanium instruments. METHODS: ProGlider (#16/progressive taper; Dentsply Sirona, Ballaigues, Switzerland), One G (#14/.03; Micro-Mega, Besancon, France), and EdgeGlidePath (#16/progressive taper; Edge Endo, Albuquerque, NM) were tested. For the bending stiffness test, the instrument was bent to a 45° angle along the main axis while 3 mm of the tip was secured. Cyclic fatigue resistance was measured during pecking movement, whereas the file was rotated within a reproducible simulated canal with a 3-mm radius and a 90° angle of curvature. The ultimate torsional strength and toughness were evaluated using a custom device. While tightly holding the end of the file at 3 mm, a rotational load of 2 rpm speed was applied until fracture. The results were analyzed using 1-way analysis of variance and Tukey post hoc comparison. A microscopic inspection was performed on the surface of a separate instrument using a scanning electron microscope. RESULTS: EdgeGlidePath showed superior cyclic fatigue resistance compared with the other systems. One G showed higher maximum torsional strength than the others. One G showed the largest distortion angle and the highest toughness followed by EdgeGlidePath and ProGlider (P < .05). One G also showed larger bending stiffness than the others, whereas EdgeGlidePath showed a larger residual angle than the others (P < .05). CONCLUSIONS: Conventional wire showed higher toughness and torsional resistance than M-Wire and heat-treated nickel-titanium instruments. However, heat-treated wire showed higher cyclic resistance than conventional wire and M-Wire.
INTRODUCTION: The aim of this study was to compare the cyclic fatigue, torsional resistance, and bending stiffness of single-file glide path preparation nickel-titanium instruments. METHODS: ProGlider (#16/progressive taper; Dentsply Sirona, Ballaigues, Switzerland), One G (#14/.03; Micro-Mega, Besancon, France), and EdgeGlidePath (#16/progressive taper; Edge Endo, Albuquerque, NM) were tested. For the bending stiffness test, the instrument was bent to a 45° angle along the main axis while 3 mm of the tip was secured. Cyclic fatigue resistance was measured during pecking movement, whereas the file was rotated within a reproducible simulated canal with a 3-mm radius and a 90° angle of curvature. The ultimate torsional strength and toughness were evaluated using a custom device. While tightly holding the end of the file at 3 mm, a rotational load of 2 rpm speed was applied until fracture. The results were analyzed using 1-way analysis of variance and Tukey post hoc comparison. A microscopic inspection was performed on the surface of a separate instrument using a scanning electron microscope. RESULTS: EdgeGlidePath showed superior cyclic fatigue resistance compared with the other systems. One G showed higher maximum torsional strength than the others. One G showed the largest distortion angle and the highest toughness followed by EdgeGlidePath and ProGlider (P < .05). One G also showed larger bending stiffness than the others, whereas EdgeGlidePath showed a larger residual angle than the others (P < .05). CONCLUSIONS: Conventional wire showed higher toughness and torsional resistance than M-Wire and heat-treated nickel-titanium instruments. However, heat-treated wire showed higher cyclic resistance than conventional wire and M-Wire.
Authors: Jorge N R Martins; Duarte Marques; Isabel Vasconcelos; Sofia Arantes-Oliveira; João Caramês; Francisco Manuel Braz Fernandes Journal: Dent J (Basel) Date: 2022-02-17