Biomechanical properties, Finite element analysis, Kalra Simultaneous Intrusion and Retraction loop, Omega loop, T loop, Tear drop loop, Titanium molybdenum alloy
Citation Information :
Francis P, Haris TM, Margaret VA, Roshan G, Menon V, Jojee V. Evaluation of Biomechanical Properties of Four Loops at Different Activation: A Finite Element Method Study. J Contemp Dent Pract 2018; 19 (7):778-784.
Aim: The aim of the study was to evaluate the force, moment, and moment/force ratio (M/F) generated by activating T loop, Kalra Simultaneous Intrusion and Retraction (KSIR) loop, Omega loop, and Teardrop loop made of titanium molybdenum alloy (TMA) wire with different preactivation bends at 1, 2, and 4 mm activation.
Materials and methods: Finite element method (FEM) models of the four loops were created and different preactivation bends were placed. The loops were then activated and analyzed for force, moment, and M/F ratio using ANSYS software.
Results: In loops without preactivation bends, highest force values were generated by Omega loop, whereas T loop had the least force value. The mean value for the M/F in the alpha segment was almost similar. In loops with preactivation bend, the force was highest in Teardrop loop, whereas T loop had the least force value. The mean value for the M/F in the alpha segment was almost similar in all the loops.
Conclusion: T loop with preactivation bend shows the most favorable properties.
Clinical significance: T loop is comparatively reliable for the frictionless mechanics for the space closure than the other loops evaluated in clinical use.
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