Effect of different torques in cyclic fatigue resistance of K3 rotary instruments

• Autor(a) principal: Kawakami, Dirce Akemi Sacaguti
• Data de Publicação: 2015
• Outros Autores: Candeiro, George Táccio de Miranda, Akisue, Eduardo, Caldeira, Celso Luiz, Gavini, Giulio
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Brazilian journal of oral sciences (Online)
• Texto Completo: https://periodicos.sbu.unicamp.br/ojs/index.php/bjos/article/view/8640825
• topic: Dental instruments; Endodontics; Fatigue; Root canal preparation; Torque; Odontologia

Aim: To assess the effect of different torque values on cyclic fatigue resistance of K3 rotary nickeltitanium (NiTi) files. Methods: Eighty K3 files, size 25 mm, taper 0.04 were divided in 4 groups according to different torques (0.5, 1, 2 and 6 Ncm) and were submitted to a cyclic fatigue test. This test was performed with a device that allowed the file to rotate inside a stainless steel artificial curved canal, simulating the pecking motion. Files rotated until fracture occurred and time to failure was recorded in seconds with a stopwatch. Data were analyzed by ANOVA and Tukey tests (p<0.05). Results: All groups were compared and only the group of 6 N.cm showed statistically significant difference (p=0.0002). Conclusions: For #25.04 K3 files, the evaluated torques up to 2 N.cm had no influence on cyclic fatigue resistance. Using 6 N.cm torque value resulted in lower resistance to cyclic fatigue.