Orthodontics is the branch of dentistry that deals with the diagnosis, prevention and correction of dental misalignments occurring as a result of crooked or crowded teeth, missing of extra teeth, incorrect jaw function due to an over-, under- or cross-bite. Fixed and removable appliances like braces and aligners are the tools of choice to help the patient to correct the misalignment. Fixed appliances can’t be taken out for cleansing. Therefor a correct oral hygiene is very important. The treatment begins often between the age 11 to 12, but can treat dental misalignments during the whole life and also in adult age.