If you have a permanent retainer on the bottom row of teeth, do you floss above and below the wire or just under the wire?

You must floss above and below, using a threader under the wire between the teeth. This is very important to prevent bone loss. Best wishes, a good question

flossing is one of the best ways but you can buy a interdental brush that is small to get into the small spaces between the lower teeth both upper and lower areas .any pharmacy has an assortment of disposable brushes.