title: Influence of sodium hypochlorite on mechanical properties of K3 nickel-titanium rotary instruments.
abstract: Several studies have evaluated the influence of various factors on the fracture of nickel-titanium endodontic rotary instruments. The present study analyzed the influence of sodium hypochlorite on flexural fatigue and torsional properties of nickel-titanium endodontic rotary instruments. New files and files previously exposed to sodium hypochlorite were tested for flexural fatigue and for resistance to fracture by twisting. The t test was used to compare the groups for number of cycles, angle of rotation, and maximum torque required to fracture. No statistical difference existed between these groups. Scanning electron microscopy analysis showed no evidence of localized corrosion in files exposed to sodium hypochlorite solution. These results suggest that the exposure to sodium hypochlorite has no influence on resistance to fracture of K3 rotary instruments.
authors: Department of Metallurgy and Materials, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors: Fabiola
authors: F
authors: Ormiga Galvão Barbosa
authors: José
authors: J
authors: Antônio da Cunha Ponciano Gomes
authors: Marcos Cesar
authors: MC
authors: Pimenta de Araújo
mesh_terms: D003343:Corrosion; D003722:Dental Alloys; D003762:Dental Instruments; D003799:Dental Stress Analysis; D004868:Equipment Failure; D008855:Microscopy, Electron, Scanning; D009532:Nickel; D010084:Oxidation-Reduction; D018583:Pliability; D012388:Root Canal Irrigants / Q000737:chemistry*; D018915:Root Canal Preparation / Q000295:instrumentation*; D012973:Sodium Hypochlorite / Q000737:chemistry*; D014025:Titanium; D019415:Torque
chemical_list: D003722:Dental Alloys; D012388:Root Canal Irrigants; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium; D012973:Sodium Hypochlorite