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Power chain (elastomeric chain) is a rubbery chain placed underneath the wires to help consolidate or close spaces between the teeth. Power chains come in various lengths and can be used on just a few teeth or all the teeth at once. Power chains are usually only used later in treatment once you've progressed to a strong enough wire to resist buckling under their force. Traditional braces require that power chains be placed on top of the wires whereas with Damon braces the power chain is placed underneath to eliminate unwanted friction and discomfort.