The system works by using a series of hard plastic trays to gradually move the teeth back into alignment. The amount of work needed will determine how many trays are needed to complete the process. Anywhere from 11 to 24 trays may be required to complete the treatment plan. In some cases, a second treatment plan may be needed to achieve the desired results. Each tray in the series moves the teeth a little more than the previous one. Trays are worn for approximately two weeks at a time. Depending on the situation and how quickly the doctor wants to make the correction, the trays may be worn up to a month a time, if needed.
Impressions of the patient's teeth are made, and a mold is created. Photographs and dimensions of the mold are fed into a computer which produces three-dimensional images of what each Invisalign® tray will be able to achieve. From those images, a series of trays will be crafted using specific molds that are made to represent the patient's teeth. Each tray in the series will be slightly different from the one that was used before it. The trays are designed to snap firmly into place over the lower sections of the tooth. Trays are made of an extremely hard, clear plastic that cannot be seen once the tray has been snapped into place.
The length of an Invisalign® treatment plan will be determined by how much work needs to be performed. If only a minimal amount of correction is needed, the treatment plan may last as little as ten months. If extensive work needs to be done, a 24-month treatment plan may be needed. In some cases, correcting one issue may cause another to present itself. If that occurs, the dentist may formulate a second treatment plan to help achieve the desired goal. The dentist will carefully monitor the use of the trays to determine how well they are working and how close the patient is to the smile they have always wanted.