An orthodontist, or general dentist, begins by taking dental impressions, x-rays and photographs of the patient’s teeth and sending them to Align Technology. The impressions are put through a CT scan from which a computer creates a three-dimensional model. Technicians then individualize the teeth in the computer model and move them to their final position as prescribed by the orthodontist. Custom software then simulates the movement of the teeth in stages. The orthodontist reviews the simulation online using Align Technology’s ClinCheck via a web browser and approves or modifies the treatment. Once approved, a plastic resin aligner is manufactured for each stage of the computer simulation and shipped to the orthodontist.
Attachments are sometimes bonded to teeth that need to be rotated or moved more than other teeth. Patients can expect as many as fourteen attachments. They are tooth-colored and made of composite material (material is also used to fill cavities). Elastic wear (rubber bands) are also used to move the teeth forward or back relative to the jaw, thus accomplishing anterior or posterior corrections or intrusions and ectrusions. Reproximation, (also called Interproximal Reduction or IPR and colloquially, fileing or drilling), is sometimes used at the contacts between teeth to allow for a better fit.
Average treatment time is about one year, again depending on the complexity of the treatment. Simple treatments (minor crowding, minor spacing) may be as short as twenty weeks—this is known as the “Invisalign Express” program. Although the aligners are removable, they must be worn at least 20 to 22 hours per day to avoid delaying the treatment process. If they are not worn consistently, treatment time will increase.
After the regular aligner or braces treatment is complete, retainers composed of a similar plastic material are usually required to be worn, at least at night.
Like other orthodontic systems, the patient has some flexibility. The final position of the teeth is not completely determined by the last aligner. If the patient wants to change the end position because the actual position is not optimal, new aligners are ordered, which are usually included in the originally quoted cost, called a ‘Refinement.’
Invisalign has a teen line that is appropriate for patients who have shed all of their baby teeth and have second molars at least partially erupted.
