A study of force extension and force degradation of orthodontic latex elastics: An in vitro study

The purpose of this study was to determine the force values of different orthodontic latex elastics at different extensions when subjected to testing in dry and wet conditions. This study also aims to determine and compare the force degradation of the elastics produced by four manufacturers at different extensions and at regular intervals. Materials and Methods: 5/16 inch lumen medium (Green) and ¼ inch lumen medium elastics (blue) of 4 companies were used. The elastics were stretched on a correx gauge to two times and three times the inner lumen diameter and at a fixed distance of 25 mm (dry test).The elastics were stretched at the specific distances and then immersed in artificial saliva and checked after 24 and 48 h (wet test). The data was analyzed using Student′s t-test. Results: Force degradation increases with time. Force degradation percentage values vary from 5% to a maximum of 25%. Conclusions: Thus from the study, the clinician can know the force degradation rates of elastics of two different sizes, manufactured by four different companies. This study also shows that though, the force degradation during the 2 nd day was found to be significant in most of the elastics, it is not sufficient to justify daily change of elastics