J. Phys. IV France 07 (1997) C5-661-C5-665
Effect of Temperature on Torsional Properties of Ni-Ti and Copper Ni-Ti Orthodontic WiresM.P. Filleul1, 2, R. Portier1 and L. Jordan1, 3
1 Laboratoire de Métallurgie Structurale, ENSCP, 11 rue Pierre et Marie Curie, 75231 Paris cedex 05, France
2 Faculté de Chirurgie Dentaire, Université René Descartes Paris V, Paris, France
3 Faculté de Chirurgie Dentaire, Université Denis Diderot Paris VII, Paris, France
The behaviour of Ni-Ti and Copper Ni-Ti orthodontic wires was tested under induced torsion in controlled conditions of moment and temperature. The results clearly demonstrate a great difference in the behaviour of these wires. The loading and unloading curves and plateau regions were found to be closely related to temperature. Experiments carried out in conditions of identical torsion revealed significant variations in stiffness due to changes in mouth temperature. Diversity of reaction to stress is linked to the crystalline structure of the alloys.
© EDP Sciences 1997