Evaluation of latex and non-latex intermaxillary elastics strength degradation when submitted to the use of chlorhexidine

ABSTRACT Purpose: To assess the influence of 0.12% chlorhexidine solution (CHX) in the strength degradation of different intermaxillary latex and non-latex elastics. Materials and methods: Eighty ¼ inch elastics were separated into eight groups (n = 10) according to manufacturers (Morelli™ and American Orthodontics™), elastic’s type (latex and non-latex) and storage solution (artificial saliva and CHX). Each sample was extended to 19.2 mm, corresponding to 3x the size of their inner diameter, and initial force was verified on the universal testing machine. The elastics were then kept extended, immersed in artificial saliva and their strength was once again evaluated in the following period of time: 12 and 24 hours. Following the storage period, elastics of CHX groups were immersed for 1 min into PerioGard (0.12% chlorhexidine solution) before the strength evaluation. The data (gf) was submitted to a three-way repeated measure analysis of variance and Tukey’s test (α = 0.05). Results: Significant differences between elastics and time were observed (p < 0.000). Statistically significant reduction in strength was found in non-latex and latex elastics between the initial condition and after 12 h and 24 h (p < 0.05). The non-latex elastics showed statistically higher degradation values than the latex elastics, in the three analysis times (p < 0.05). No statistical difference was found between saliva and CHX, regardless of the time and elastic type (p > 0.05). Conclusions: Generally, the latex elastics showed less strength degradation compared to non-latex elastics. CHX did not affect strength degradation and time influenced strength degradation in the first 12 hours, keeping practically constant for up to 24 hours.