After impression formation, the stone of the laboratory is poured into your impression to create a stone model of your teeth. Once hardened and trimmed, it is placed on a "suction" machine, heated a layer of plastic, discarded on the model, and the vacuum is used to form around the teeth. Then insert it on your teeth. If a dentist has the right equipment, he/she can do it in their office or train an assistant to do it. If not, they can send it to the dental laboratory without any certification to make it, but there is a legislative requirement that only a dynamic practitioner can make an impression.
I am not very familiar with invisalign technique, but it does require a more orthodontics experience, because the teeth need but use a wax or clip to decorate, so as to put pressure on them to move them. Sometimes, use bleach to put the "resovoirs" in front of your teeth and add a composition to make a spot for bleach.
