One Aligner Is Missing. Call Before Switching
Contact the treating team when an aligner is lost, cracked or distorted. Give the tray number and wear history before changing the sequence.
Gather the useful details
Tell the office which aligner is missing or damaged, whether it is the upper or lower tray and how long you wore it. The AAO advises contacting the treating orthodontist promptly because aligners follow a planned sequence.[2]
Keep the packaging and any previous trays available. Ask which, if any, should be worn while a replacement or review is arranged. Do not jump ahead or return to an old tray based solely on how close the numbers look.
Do not force a damaged tray
The AAO advises against wearing an appliance that is sharp, painful or badly distorted. Do not heat, glue or trim it to make it fit. A photo through the office's approved channel may help the team triage the problem, if they request one.[1]
Confirm whether your change date or next appointment needs adjustment, and ask about replacement fees. Afterwards, keep the case with your daily essentials. If trays are repeatedly lost or wear time is difficult, discuss the routine openly so the plan can be reviewed.