Invisalign orthodontic aligners are thin, clear plastic appliances that has been custom-molded so they fit snugly over the wearer's teeth. They can look very similar to the dental bleaching trays that dentists make for their patients so they can perform at-home teeth whitening treatments. In most cases, however, orthodontic aligners are made out of a thinner, stiffer type of plastic and one that is more optically clear (and therefore is less noticeable when worn). Invisalign aligners are also very similar, almost precisely so, to the clear plastic vacuum-molded orthodontic retainers that are sometimes worn by patients once they have completed their orthodontic treatment.

Invisalign aligners should be worn around the clock except for those times when the patient is eating, drinking or brushing and flossing. For a person with normal habits, it is expected that they will be wearing their aligners on the order of 22 hours per day.

Clear braces can be removed for special events and occasions but any patient needs to understand that their treatment cannot progress unless their aligners are worn. Not wearing their aligners as directed will increase the length of the person's total treatment time, or worse, allow for a relapse of previous orthodontic progress. The latter can seriously complicate or compromise the original treatment plan, sometimes to the point where a new set of orthodontic aligners must be created.

In most cases orthodontic treatment utilizing Invisalign clear braces will take about as long as the same treatment would with traditional braces. Some published reports do, however, suggested that Invisalign treatment could be more rapid.