Invisalignappliance is recommended for youth and adults. This device is a set of transparent overlays that must be worn 22h / day (round the clock with breaks for meals). Depending on the severity of the defect, the entire treatment covers several to several dozens of overlays. They are changed every 10-14 days. An orthodontist on follow-up visits monitors the progress of treatment and issues 3-4 overlays, which the patient independently changes in accordance with the recommendations. These devices facilitate the maintenance of hygiene during treatment and are a great solution for patients living abroad.