THE EFFECT OF ENVIRONMENTAL FACTORS ON ELASTOMERIC CHAINS AND NICKEL TITANIUM COIL SPRINGS

It is well known that elastomers exhibit viscoelasticity and as such have their mechanical properties modified by temperature. Nickel titanium archwires are also affected by temperature and have been modified with specific temperature related properties for clinical use. What is less well known is the effect that other environmental factors, such as food, might have on the force delivery properties of both elastomeric materials and nickel titanium coil springs used for space closure. The aim of this work was to determine the effect three common environmental factors coca cola, refined sunflower oil, and pasteurized milk have on elastomeric chain and nickel titanium coil springs. In addition, it was decided to re-examine the effect of temperature at 22 C, 36,6 C, and 55 C on both these space closing materials. Degradation force measurements were made at the following intervals: 0, 1, 7, 14, 21, and 28 days. The results indicated that elastomeric chains were affected by all the test food liquids while nickel titanium springs were more affected by low temperature.