Denture teeth in Invisalign tray can be a challenge
The easiest thing to do would be place filling material or acrylic in the missing tooth space. A denture tooth works as well, but can be a challenge going from tray to tray. Few have mentioned that popping them in and out was effective or convenient, often they need to be secured to each aligner. If they are secured very well to the tray, they are difficult to remove.
$30-50 per tooth should be expected, but you may need to purchase more than one if one gets stuck in a...