Invisalign Tray 1 Lost on Day 2. Is It Ok to Advance to Tray 2?

Considering it is your first tray, I think you will be ok by advancing to the aligner 2.  Consider wearing aligner 2 for 3 instead of 2 weeks and be prepared for some discomfort.  Take tyenol if needed.  Whatever you do, do not go without an aligner for more than 24hours. 

The best thing is to check with your doctor.

It is very easy to order a new tray. Usually the first tray lost is free.This is our office policy.

The short answer, typically NO. If you loose any Invisalign tray the default action should be to go back to your previous tray, if you can ot reach your orthodontist.

A replacement tray for the lost one can be order over the phone and arrive at the office approx 5 working days.

By going back to your last tray you avoid prematurely exerting force on a tooth that was not in the correct position to receive it. If a pressure is applied too early to a tooth while in Invisalign that tooth can actually move in the wrong direction, adding time and often cost to treatment.

Sometimes, based on the orthodontist knowledge of the movement sequence, they may OK moving fwd in a tray. In general, if the tray is completely "flush" then a day or two early is not a big deal, I would never move through tray faster than 1.5 wk even if teeth are flush.