BACKGROUND : Orthodontic treatment has a significant impact on the quality of life and self-esteem of adolescents, with emotional and behavioral implications. The objective of this research was to understand Brazilian adolescents' perception of the orthodontic treatment. METHODS : A qualitative research study was carried out through content analysis of data collected from 142 adolescents using the word-association technique (WAT), followed by 8 focus groups with 71 of these students. RESULTS : The most recurrent words on the WAT demonstrated a positive esthetic impact of the orthodontic appliance, both for the adolescents' self-assessment and in the assessment of friends. Several themes were identified in the qualitative analysis, with the esthetic benefit of orthodontic treatment and the esthetic impact of the appliance being the most relevant positive points. The most-cited negative aspect in the study was the pain associated with the treatment, followed by the discomfort and trauma caused by the fixed appliance. CONCLUSIONS : Orthodontic treatment has a positive esthetic impact for Brazilian adolescents, with improvement of their self-image. Fixed orthodontic appliances have an immediate positive impact on appearance and are an important factor in behavioral relationships among Brazilian adolescents, particularly owing to their association with social status. The understanding of the sociobehavioral aspects involved in orthodontic treatment is of fundamental importance for the clinical relationship between patient and professional.