Can you straighten your teeth with ONLY retainers?

Question

(not invisalign, and no braces?)

Answer 1

No. Retainers are used to retain teeth in their current positions not change their positions.

Answer 2

yes. but you'll need to wear them a lot and to actually straighten them the doctor needs to tighten the wires on them after awhile  

Answer 3

No. A retainer does exactly what it's name implies. It retains the position of your teeth after they have already been straightened by other methods.