Biomechanical behaviors of the orthodontic wires

الملخص EN

Aims : To evaluate and compare the yield, ultimate and failure stresses of the untreated and the treated super-elastic Nickel titanium and Spring hard stainless steal orthodontic arch wires with artificial saliva for one, two and four weeks.

Materials and Methods: The sample consisted of four groups (10 wires for each group): the control group, one, tow and four weeks of emersion in artificial saliva groups, for each of the nickel titanium and spring hard stainless steal orthodontic arch wires.

The specimens were tested with tensile procedure and plotted the load stress-strain curve, from this curve the yield, ultimate and failure stresses elasticity modulus can be calculated.

The data were subjected to the descriptive statistics, ANOVA and Duncan’s analyses at p ≤ 0.05 significant level.

Results : The biomechanical properties (yield, ultimate and failure stresses) of Super-elastic Nickel titanium and Spring hard stainless steal orthodontic arch wires demonstrated significant decrease as the immersion time in artificial saliva increased.

Conclusions : The orthodontic arch wires (super-elastic nickel titanium and spring hard stainless steal) are recommended to be used intra-orally for short period to avoid reaching the complete loss of the biomechanical properties.