EN
Orthodontic treatment aims at restoring correct occlusion and chewing function and improving the aesthetics of the dentition and facial esthetics of the patient. During treatment complications may occur. Most frequently observed complications have been described in the paper.There role of the orthodontist in the therapeutic process and the principles on which doctor- patient cooperation should be based in order to achieve a therapeutic success have been presented. Particular emphasis has been put to the importance of prevention of dental caries and periodontal diseases in orthodontic patients.