37 - Behavior of orthodontic elastic ligatures with variation in internal diameter in tensile tests

Abstract

Orthodontic elastics are essential for tooth movement, since their stress-strain properties allow them to transform elastic potential energy into mechanical energy, producing tooth movement. These elastics are available in a wide variety of types on the dental market and have variations in their dimensions from the same commercial brand or different brands. The objective of this study was to evaluate how the variation in the internal diameter of orthodontic elastic ligatures of 4 different commercial brands influences their fixation capacity, using simulations of first-order-bends in tensile tests with progressive magnitudes. The study evaluated the relationship between the internal diameter of orthodontic elastics and the force generated in tensile tests. A total of 240 samples of the brands Uniden, Morelli, Orthosouce and Unitek were tested. Previously, their dimensions were measured under a light microscope and tested in simulations of first-order orthodontic bends, varying between tractions of 0.5 mm, 1.0 mm and 1.5 mm, in a universal testing machine. Subsequently, the relationship between the dissipated force and the dimension of the internal diameter was investigated. In force tests of 0.5 mm, the groups of Unitek, Morelli and Orthosource elastics were significantly stronger than the Uniden. In tractions of 1.0 mm and 1.5 mm, the Unitek elastic presented the greatest force, followed by the Morelli and Orthosource elastics, with no statistical differences between them, and lastly the group of Uniden elastics. When subjected to correlation tests, there was no statistical significance in any of the correlations. The study concluded that there is no significant influence of the internal diameter on the fixation effectiveness of orthodontic ligatures.