Variation of the superelastic properties and nickel release from original and reused NiTi orthodontic archwires.
J Mech Behav Biomed Mater
; 6: 113-9, 2012 Feb.
Article
en En
| MEDLINE
| ID: mdl-22301180
ABSTRACT
Reuse of NiTi orthodontic wires has become increasingly common in dental clinics. For sterilization and recovery of the original superelastic properties of the wires, a heat treatment is usually performed between 500 and 600 °C. The aim of this study was to analyze the effect of these thermal treatments on the mechanical behavior and the microstructure of NiTi archwires of different compositions. A reduction of the Ni content was observed in the matrix of the thermally treated archwires, due to the formation of Ti(3)Ni(4) precipitates. The nickel-rich precipitates were observed and characterized by Transmission Electron Microscopy (TEM) and electron diffraction. They were found to alter the mechanical properties of the wires, decreasing the transformation stresses, and causing a loss of activation of the NiTi archwires. The release of nickel was higher in the original archwires than in the reused ones, due to the matrix nickel depletion caused by the precipitation of Ti(3)Ni(4).
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Alambres para Ortodoncia
/
Titanio
/
Elasticidad
/
Níquel
Idioma:
En
Revista:
J Mech Behav Biomed Mater
Asunto de la revista:
ENGENHARIA BIOMEDICA
Año:
2012
Tipo del documento:
Article
País de afiliación:
España