Determination of the flexural modulus of elasticity of orthodontic archwires.
OBJECTIVE
To design a protocol for the determination of the flexural modulus of elasticity of wire with high accuracy and precision.


METHODS
Cantilever bending was used at long span and low loads, using a laser displacement sensor. Various wires were tested for proof-of-concept: stainless steel, Elgiloy, Wiptam and a gold alloy, with primary attention being paid to the source and magnitude of errors.


RESULTS
The moduli of elasticity were determined with a median relative error of approximately 0.15%, with a worst case of 0.56%, taking into account all measurement errors. The precision was such as to permit distinctions between the values for the wires of different thermomechanical history.


CONCLUSIONS
The determination of the elastic modulus of wires may be made with good precision using cantilever bending providing attention is given to all sources of error. These results represent the most reliable measures of modulus of elasticity of orthodontic archwires to date.
Tian
Kun
K
Independent Section of Radiology, Semmelweis University, Budapest, Hungary.
Darvell
Brian W
BW
D003722:Dental Alloys; D003799:Dental Stress Analysis / Q000295:instrumentation / Q000379:methods*; D055119:Elastic Modulus; D008422:Materials Testing; D009969:Orthodontic Wires; D018583:Pliability; D015203:Reproducibility of Results; D013314:Stress, Mechanical
D003722:Dental Alloys