Changes in the Force Decay of Orthodontic Elastomeric Chains after Immersion in Different Mouthrinses

Objective: To investigate the influence of the most frequently utilized mouthrinses on the force degradation of different elastomeric chains. Methodology: Conventional and memory elastomeric chains were attained from two different manufacturers with a total of 320 specimens. Each of the 4 chain types was divided into two groups to deliver light (200g) and heavy forces (350g) (n= 40). Each group was further divided into 4 subgroups (n=10): a control one where the elastomeric chains were immersed in deionized water and three experimental groups immersed in a sodium fluoride (NaF) containing mouthrinse, a whitening mouthrinse and an alcohol containing mouthrinse. The force decay percent was measured over 5 time points. Results: Force decay was significantly higher in alcohol containing mouthrinse group at day 1 compared to other groups followed by a marginal significance. In the whitening group; force decay was non-significantly higher than that in sodium fluoride followed by the control group . There was no significant difference in force degeneration between the two companies. In conventional chain group; there was a significantly higher force decay (p<.001) compared to memory one with the greatest decrease in the first day till the second week, then both reached a plateau and the force remained nearly constant at weeks 3 & 4. No significant difference was detected between light and heavy force application. Conclusion: Alcohol containing mouthrinses can intensify force decay in elastomeric chains more than bleaching and NaF mouthrinses. Memory elastomeric chains are recommended as they exhibited less force decay compared to conventional ones.