Influence of Sodium Hypochlorite on Mechanical Properties of K3 Nickel-Titanium Rotary Instruments

• Published in: Journal of endodontics Vol. 33; no. 8; pp. 982 - 985
• Main Authors: Ormiga Galvão Barbosa, Fabiola, Antônio da Cunha Ponciano Gomes, José, Pimenta de Araújo, Marcos Cesar
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.2007
• Subjects: Corrosion; Dental Alloys; Dental Instruments; Dental Stress Analysis; Dentistry; Endocrinology & Metabolism; Endodontic instrument; Equipment Failure; fracture; Microscopy, Electron, Scanning; Nickel; nickel-titanium; Oxidation-Reduction; Pliability; Root Canal Irrigants - chemistry; Root Canal Preparation - instrumentation; sodium hypochlorite; Sodium Hypochlorite - chemistry; Titanium; Torque; Endodontic instrument; nickel-titanium; sodium hypochlorite; fracture
• ISSN: 0099-2399; 1878-3554
• DOI: 10.1016/j.joen.2007.05.008

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.