Invisalign is a removable orthodontic appliance offered as an alternative to more traditional orthodontic solutions. A type of clear tooth aligner, Invisalign is intended for people who find the idea of a mouthful of metal braces and brackets – however effective – too unattractive to commit to. If you’re a candidate, you can maintain your smile aesthetics while straightening your teeth.
The use of a series of removable aligners for the adjustment of occlusion (bite) is not new. The Invisalign method is based on a concept first introduced in the 1940s and revisited in the 1970s that required a series of dental impressions to determine the optimal position of the teeth. The update method is simpler than its predecessors, requiring only one set of impressions and photographs of the teeth, taken during an initial consultation.
These impressions are used to create a three-dimensional computer projection of how the teeth could be moved incrementally, forming the basis for developing a series of custom-made aligners designed to accomplish this movement.
Invisalign aligners are manufactured at the Align Technologies dental laboratory using computer-aided design/computer-aided manufacturing (CAD/CAM) processes. The aligners are sent to the dentist, who typically dispenses them in groups of one or two at a time during regular check-up appointments (about every four to six weeks) so that treatment can be properly managed. Each aligner must be worn in its specific order for about two weeks, during which time it moves the teeth in small increments of about .25 millimeters to .33 millimeters. Although the aligners are removable (for eating, drinking certain beverages and brushing/flossing), they must be worn at least 20 hours a day in order to reposition the teeth successfully.
A typical treatment requires 20 to 30 aligners for both the upper and lower teeth. Most adults complete their treatment in less than one year. However, treatment time depends on the specific alignment problem.