Tray 50 of 67 doesn't fit and pops out. What should I do?

Hello there,I recommend following your dentist's advice as long as you are able to wear your aligner and it's not uncomfortable.  If you have the same issue with the next set of aligners, be sure to bring this to your dentist's attention again.  That way, your dentist or the lab can make adjustments if necessary.  Good luck and I hope this helps. Follow me if you have more questions.Sarah Thompson, DMDSt. Louis, MO area (O'Fallon, IL)Real Self 100

If there is no new dental work (i.e. crown, filling, etc), which could alter the fit of the aligner, there is a possibility that a manufacturer defect exisits in the aligner material.  While this is rare, it is possible.  If your dentist's recommendation does not work, schedule an appointment as soon as possible.  Additional aligners may need to be ordered.  Best of luck!