In vitro study of the stretching time-associated force magnitude generated by NiTi and stainless-steel closed coil springs

Closed coil spring is an additional tool in a fixed-orthodontic treatment. NiTi orthodontic alloy that has shape memory and elasticity features, while stainless steel properties of malleability, low friction between wire-bracket, as well easy soldering welding. Various closed springs have been widely studied, but research on the stretching time remains unclear. This study aimed to determine effect differences for 7 days, 14 21 28 days force magnitude stainless-steel (SS) spring. A x 5 1 cm acrylic blocks with posts were employed, 25 mm attached using modified T-sticks. The immersed artificial saliva pH 6.75 7, 14, 21, incubator at 37 °C. container was removed from measured universal testing machine. Kolmogorov-Smirnoff test carried out analyze parametricdata, independent T-test used difference each group. There significant SS all groups (p < 0.05). no > 0.05) there day ratio confirmed. Longer indicated loss closed-coil spring, had more stable which implies formidable treatment-time