The number of trays used in a series will depend on how much movement is required to reach the desired alignment. A series of trays can contain anywhere from 10 to 40 trays. Each tray is worn for 10 to 14 days. Once each tray has been worn for the allotted amount of time, it is put away and the next tray is ready to be used. If for some reason, an unforeseen circumstance arises, the patient can use the same tray for a slightly longer period of time if need be. The trays are easy to clean and can be taken out or put back in as needed.
A computer generated program simulates what a person’s mouth looks like when the treatment begins as well as what it will look like when the treatment is completed. The dentist will use the computer program to create a series of trays that will be used consecutively to move the teeth a little more with each progression. As the trays continue to be used, the teeth will move a little more each time until they have reached the desired goal. A retainer may need to be worn for several weeks to ensure that the teeth will not begin to shift back to their prior position. There are cases where one series of trays is not enough. A second series is created that may contain another set of trays. In most cases, when a second set of trays is needed, the number of trays decreases slightly.
While the Invisalign® system works well when it comes to moving teeth that are modestly out of alignment, there are situations where a more extensive system is needed. Individuals who have teeth that require extensive movement, and in some cases, jaw modification, the tray system will not produce the type of results that are needed to effectively restore the person’s smile or realign their teeth. Individuals who have problems with their jaw alignment may also be passed over for this type of system. In order to use the tray system, the main structure of the jaw and mouth should be somewhat normal. If not, it may take several series of trays to correct the problem. Conventional braces may be able to move the teeth much faster and with much less discomfort.