Mixed my trays up. Is this OK?

As with any orthodontics it is imperative that at the end of treatment the dentist adjusts your bite. This is very important. Your sensitivity is nature's way of telling you that something isn't fitting correctly. If your dentist doesn't adjust the interference, nature will, and Nature uses...

Combining a fixed lingual bonded wire and removable clear retainers can be a great solution to ensure great alignment after completing Invisalign.

That's correct, the last 3 aligners are optional, they are called overcorrection trays that Invisalign provides for every case.  They may or may not be necessary, it just depends on the individual.  The main purpose of these trays is to close any residual spaces or gaps between the...