Invisalign

A common option to fixed braces for treating many orthodontic patients is the Invisalign system from Align Technology, Inc. This consists of a series of rigid, clear plastic trays ("aligners") which are worn over the teeth, and apply incremental forces that cause them to move over time. The aligners are all made in advance using the preliminary stone casts from the diagnostic records appointment.

The process of making the aligners involves computerized plastic forming technology as follows:

• A computerized laser scanner produces a 3-dimensional computer model of the original position of the teeth, using the stone cast replicas made by the dentist at the diagnostic records appointment.

• Specialized software is used to devise an incremental tooth-movement plan for the patient, ending with the treatment goal specified by the dentist.

•At each interim position of the teeth, a plastic forming process called "stereolithography" is used to generate a rigid, clear plastic aligner that will fit the teeth in that position. There may be dozens of aligners required to accomplish the desired tooth movement.

• The patient wears each aligner in the series until the teeth are located where the aligner fits them passively. At that point, the patient moves to the next aligner.

• The process is repeated until the patient's teeth are in the desired final location specified by the dentist.

•The retention phase of Invisalign treatment simply consists of wearing the final aligners a certain number of hours per day as specified by the dentist without holding back. With Invisalign, there's nothing to hide.