INTRODUCTION: Recent improvements in alloys, kinematics, and concepts have been combined to increase the cyclic fatigue resistance of nickel-titanium (NiTi) instruments. The aim of this study was to compare the cyclic fatigue resistance of new M-Wire reciprocating WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) and Reciproc (VDW GmbH, Munich, Germany) files at 2 levels. METHODS: Sixty Reciproc and 60 WaveOne new files were fixed to a specifically designed device and tested in tempered steel canals with a 3-mm radius and a 60° angle of curvature. The motor used was programmed as defined by each manufacturer, and the specific reciprocating motion was followed. Thirty files of each brand were tested at 5 mm, and 30 were tested at 13 mm from their tips. The time to failure was registered. Weibull analysis was used to calculate the mean life, beta, and eta parameters. RESULTS: The probability of the mean life was higher for Reciproc than WaveOne files at both levels, with the probability of the Reciproc mean life being 62% higher than that of WaveOne at 5 mm from the tip and 100% higher at 13 mm (all statistically significant). The probability of the mean life was higher at 5 mm than at 13 mm in both systems. The results may have been partially conditioned by the different motions that manufacturers propose for each system. CONCLUSIONS: Reciproc files were more resistant to cyclic fatigue than WaveOne files at both distances from the tip. Both systems had greater cyclic fatigue resistance at 5 mm than at 13 mm from the tip.
INTRODUCTION: Recent improvements in alloys, kinematics, and concepts have been combined to increase the cyclic fatigue resistance of nickel-titanium (NiTi) instruments. The aim of this study was to compare the cyclic fatigue resistance of new M-Wire reciprocating WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) and Reciproc (VDW GmbH, Munich, Germany) files at 2 levels. METHODS: Sixty Reciproc and 60 WaveOne new files were fixed to a specifically designed device and tested in tempered steel canals with a 3-mm radius and a 60° angle of curvature. The motor used was programmed as defined by each manufacturer, and the specific reciprocating motion was followed. Thirty files of each brand were tested at 5 mm, and 30 were tested at 13 mm from their tips. The time to failure was registered. Weibull analysis was used to calculate the mean life, beta, and eta parameters. RESULTS: The probability of the mean life was higher for Reciproc than WaveOne files at both levels, with the probability of the Reciproc mean life being 62% higher than that of WaveOne at 5 mm from the tip and 100% higher at 13 mm (all statistically significant). The probability of the mean life was higher at 5 mm than at 13 mm in both systems. The results may have been partially conditioned by the different motions that manufacturers propose for each system. CONCLUSIONS: Reciproc files were more resistant to cyclic fatigue than WaveOne files at both distances from the tip. Both systems had greater cyclic fatigue resistance at 5 mm than at 13 mm from the tip.
Authors: Frederico C Martinho; Lilian F Freitas; Gustavo G Nascimento; Aleteia M Fernandes; Fabio R M Leite; Ana P M Gomes; Izabel C G Camões Journal: Clin Oral Investig Date: 2014-11-21 Impact factor: 3.573
Authors: Maira de Souza Carvalho; Emílio Carlos Sponchiado; Angela Delfina Bitencourt Garrido; Lucas da Fonseca Roberti Garcia; André Augusto Franco Marques Journal: Eur J Dent Date: 2015 Jan-Mar