Cyclic fatigue using severely curved canals and torsional resistance of thermally treated reciprocating instruments

• Published in: Clinical oral investigations 2018-09, Vol.22 (7), p.2633-2638
• Main Authors: Silva, Emmanuel João Nogueira Leal, Vieira, Victor Talarico Leal, Hecksher, Fernanda, dos Santos Oliveira, Marja Ribeiro Silva, dos Santos Antunes, Henrique, Moreira, Edson Jorge Lima
• Format: Article
• Language: English
• Subjects: Alloys; Dental Instruments; Dental restorative materials; Dentistry; Endodontics; Equipment Design; Equipment Failure Analysis; Materials fatigue; Mechanical properties; Medicine; Metal fatigue; Original Article; Phase transitions; Scanning electron microscopy; Stainless steel; Statistical analysis; Stress, Mechanical; Surface Properties; Torque
• ISSN: 1432-6981; 1436-3771
• DOI: 10.1007/s00784-018-2362-9

Objectives To evaluate the cyclic fatigue using severely curved canals and torsional resistance of ProDesign R (Easy Equipamentos Odontológicos, Belo Horizonte, MG, Brazil), Reciproc Blue (VDW, Munich, Germany), and WaveOne Gold (Dentsply Maillefer, Ballaigues, Switzerland) reciprocating instruments Materials and methods Twenty instruments of the ProDesign R (25/0.06) system, 20 instruments of the Reciproc Blue (25/0.08v) system, and 20 instrument of the WaveOne Gold (25/0.07v) system were used. Cyclic fatigue resistance was tested measuring the time to fracture and the number of cycles to fracture in an artificial stainless steel severely curved canal with 80° angle and a 3-mm radius of curvature ( n  = 10). Torque and angle of rotation at failure of new instruments ( n  = 10) were measured according to ISO 3630-1. The fracture surfaces of all fragments were examined with a scanning electron microscope. Results were statistically analyzed using one-way ANOVA and Tukey’s test at a significance level of p