AIM: to analyze five commercial brands of synthetic elastics (Morelli, Ormco, GAC, TP and Unitek), considering force degradation of these materials when maintained stretched continuously. METHODS: the synthetic elastics were stretched 20mm and the readings of the amount generated for elastics were done in the intervals: 1/2, 1, 6, 12, 24, 48 hours; 7, 14, 21 and 28 days. RESULTS: it was found in the first hour of activation a significant reduction on the amount of force generated for all elastics. There was a reduction in the amount of the generated force elastics of 20.31 to 38.47% in the first hour of the tests and 47.7 to 75.95% in 28 days of the activation. CONCLUSIONS: it was concluded that for the synthetic elastics the average force generated in 21 and 28 days of tests was statically similar in all samples.
Elastic; Elastomer; Elastomeric chain