Defects in rotary nickel-titanium files after clinical use.

Title	Defects in rotary nickel-titanium files after clinical use.
Authors	G Nervo, B Sattapan, J Palamara, Laurel H. Messer
Magazine	Journal of endodontics
Date	02/29/2000
DOI	10.1097/00004770-200003000-00008
Introduction	This study evaluates the types and frequencies of defects in nickel-titanium rotary endodontic files after regular clinical use. Analyzing 378 discarded files from a specialist practice over six months, it was found that nearly 50% exhibited defects. Of these, 21% were fractured and 28% had other non-fracture defects. Fractures were categorised into torsional (55.7%) and flexural fatigue (44.3%). Torsional failures, often due to excessive apical force, were more prevalent than flexural fatigue, typically resulting from use in curved canals.
Quote	G J Nervo, B Sattapan and J Palamara et al. Defects in rotary nickel-titanium files after clinical use.. 2000. DOI: 10.1097/00004770-200003000-00008
Element	Nickel (Ni) , Titanium (Ti)