What I do with the floss is rinse it off and then hang it around my contact lens solution bottle. It works for me because I take my contacts out at night, so I immediately grab the bottle. It reminds me not to get a new piece of floss. Then when the floss is no longer usable (about 5 uses, I think)… then I get a new piece.

(My husband uses mouth wash and keeps his floss around that.)

I guess if the floss is made from plastic and the toothbrush bristles are made from plastic, it’s the same. The floss would be hard to keep track of, though… maybe you can keep it attached to the dispenser until you’ve worn that section out.