I finished my Invisalign treatment about 6 months ago & was given a regular clear retainer (looked just like the Invisalign) & a bottom mouth guard for my TMJ. When I completed the treatment, I still had a slight gap between my two upper right teeth & one on my lower teeth was still slightly inverted. My dentist said that the aligners would help close the gap & finish straightening the bottom tooth. Well, it hasn't. So now she wants me to get the Vivera retainers. She says that will fix it.