I find most patients start noticing changes within the first 6-12 weeks with Invisalign. Your teeth will not move tremendously during these first weeks, but the changes should be significant enough where you will notice them and feel confident that the trays are working as expected. Each tray accomplishes a little bit of movement, which is why trays are changed frequently. Each tray does not move every tooth. Orthodontics is accomplished in planned stages. For example, in a patient that has a tremendous amount of spacing between the teeth, all of the space is not closed simultaneously, space is closed in a sequenced order to make sure the results are as ideal as possible. An amazing feature of Invisalign is the 3D virtual simulation of tooth movement that your orthodontist will likely review with you BEFORE you even start. By watching the simulation, you will be able to see the predicted tooth movement at each stage, so you know what to expect throughout your orthodontic treatment. This 3D simulation can be reviewed during the process at any time, so you can easily monitor your progress.