J. Phys. IV France 11 (2001) Pr8-565-Pr8-570
Characterization of closed nickel-titanium orthodontic coil springsT. Langeron1, M.P. Filleul1, 2 and J. Van Humbeeck3
1 Faculté de Chirurgie Dentaire, Université René Descartes, Paris V, 102 rue Pierre Butin, 95300 Pontoise, France
2 Laboratoire de Métallurgie Structurale, ENSCP, 75031 Paris, France
3 Faculteit Toegepaste Wetenschappen, Metaalkunde en Toegepaste Materialkunde, Katholieke Universiteit Leuven, de Croylaan 2, 3001 Heverlee, Belgium
Nickel-Titanium orthodontic coil springs are used to move teeth with low forces and slow deactivation. The present paper provides data on transfomation temperatures and on load-deflection rate at buccal temperature of closed Nickel-Titanium coil springs available on the market from ORMCO® and GAC®. All the springs exhibited superelasticity but their properties were not stable in the range of buccal temperatures and varied not only from one manufacturer to the other but they also varied from one batch to the other of each supplier. The need for more stability is stressed.
© EDP Sciences 2001