Objective: To evaluate the force decay characteristics of nonlatex vs latex interarch elastics within the normal range of salivary pH levels. Materials and Methods: Two nonlatex groups and one latex quasi-control group were tested. Elastics were stretched to 15 mm and were held for 10 seconds (baseline), 4 hours, 8 hours, and 12 hours in artificial saliva solutions with pH levels of 5.0, 6.0, and 7.5. Force magnitudes were measured at 25 mm of activation. Each specimen was used once. Measurements were assessed using three-way analysis of variance (ANOVA). Results: The three-way interaction between group, pH, and time was not significant (P 5 .13); the group-by-pH interaction also was not significant (P 5 .70). However, pH-by-time (P 5 .0179) and group-by-time (P 5 .0001) interactions were significant.