Effect of temperature on tensile force of orthodontics power chain in artificial saliva solution

The objective of this study was to determine the effect of temperature and artificial saliva solution on the tensile force of orthodontic power chains. We studied 56 orthodontic power chain specimens (Ormco, Orange, CA, USA), the closed type, that were stretched at 100% of the initial length (40 mm). Each group was stretched on an acrylic plate immersed in artificial saliva solution and Aqua Dest for 210 minutes. The tensile force was measured using a Correx meter force gauge with units of grams-force (gf) at the initial and final immersion. The temperatures used in this study were 4°C obtained from the refrigerator, 23°C from storage at room temperature, 37°C from storage in an incubator, and 55°C from heating with a hot plate. Our results showed a significantly decreased tensile force (P < 0.05) at various immersion temperatures. The effects of the immersion medium (artificial saliva solution and Aquadest) resulted in a significant decline in tensile force at 23°C (P < 0.05), but the results at 4°C, 37°C, and 55°C were not significantly different.