Color stability and force decay of clear orthodontic elastomeric chains: An in vitro study

To compare the percentage force decay of clear and semi-clear elastomeric chain products from eight different manufacturers and to evaluate the amount of discoloration after immersion in colored dietary media of the same elastomeric chain products.

An in vitro study was designed using an electronic force gauge to measure six samples from each of 19 types of elastomeric chains stretched for a period of four weeks. A spectrophotometer was used to measure the color of each specimen (10 of each type) at baseline and after being soaked in a dietary medium (coffee, tea, cola, and wine in 250 ml amounts) for 72 h.

There was a significant difference in the percentage of the lost initial force between all the tested E-chains (P<0.001). ANOVA shows a significant difference in the amount of discoloration between the E-chain types (P<0.001). Semi-clear (tooth-color/pearl/obscure) E-chain types (TP-ToothC, OrthO-Pearl, GAC-SiliPearl, 3M-Obscure) present significantly less change in color than clear E-chains of the same brand (TP-Clear, OrthoO-Clear, GAC-SiliClear, 3M-Clear).

Significant differences in the mean percentage force decay between the 19 studied clear elastomeric chain types were present. AO-Memory and Ormco maintained most of their original force at the end of the four-week interval. Significant differences in discoloration also exist between the various types of E-chains. TP Orthodontics (Tooth-Colored, SuperSlick, Clear) and Ortho Organizers (Pearl) showed the least discoloration.