Lost Invisalign Tray - Can I Advance Early?

Trays for Invisalign SHOULD be changed every 2 weeks, but in a pinch, one week should be fine.  Sometimes the next aligner is worn for 3 weeks to resume the orignal timeframe, but I don't think it is critical to do so.

Replacement aligners can take a few weeks to be fabricated, so my advice would be to move on to the next one.

It depends on where you are in the
progression of your treatment, how long you have wore the aligner that you lost
and your specific case. You should talk to your doctor before advancing early.
Most of the time it is okay to do so.

Sometimes this is the case..You can try in your next set of aligners and see how  they fit? Dont break them trying to force them in early. If they snap right in and the seat all the way down into place then you should be fine..If it feels odd then you need replacement aligners. That takes afew weeks of time..You should always save all your aligners due to this reason alone..SAVE,SAVE,SAVE all your aligners.