title: Scanning electron microscope observations of new and used nickel-titanium rotary files.
abstract: The appearances of the tip sections of ProFile 0.04 taper and Lightspeed 25-mm long, ISO size 25, nickel-titanium rotary instruments were compared with a scanning electron microscope in the as-received condition and after one, three, and six simulated clinical uses to prepare mesial canals of extracted mandibular molars. For the used ProFile instruments, there was some flattening of the characteristic material rollover and minor apparent wear at the edges of the flutes, but there was little change in the tip regions of the used Lightspeed instruments. Deposits on the surfaces of the instruments were attributed to the manufacturing processes and the in vitro preparation of root canals in the extracted teeth. The simulated clinical use did not cause substantial changes in the regions of these two brands of rotary instruments that are involved in the clinical preparation of root canals.
authors: Dental Materials Science Program, Prosthodontics and Endodontics, College of Dentistry, The Ohio State University, Columbus 4328-2357, USA.
authors: Satish B
authors: SB
authors: Alapati
authors: William A
authors: WA
authors: Brantley
authors: Timothy A
authors: TA
authors: Svec
authors: John M
authors: JM
authors: Powers
authors: John C
authors: JC
authors: Mitchell
mesh_terms: D003343:Corrosion; D003722:Dental Alloys; D003762:Dental Instruments; D004577:Electron Probe Microanalysis; D004868:Equipment Failure; D017743:Equipment Reuse; D006801:Humans; D008855:Microscopy, Electron, Scanning; D008963:Molar; D009532:Nickel; D018915:Root Canal Preparation / Q000295:instrumentation*; D013499:Surface Properties; D014025:Titanium
chemical_list: D003722:Dental Alloys; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium