[Show abstract][Hide abstract] ABSTRACT: AIM: To assess the prevalence and severity of malocclusion and orthodontic treatment needs in adolescents from the northeast of Brazil aged between 12 and 18 years.STUDY DESIGN: Cross sectional study.MATERIALS AND METHODS: The study population was composed by 300 adolescents (47.7% were males, 52.3% females). MAIN MEASUREMENTS: Information regarding occlusal alterations (Dental Aesthetic Index, DAI) and subjective perceptions on occlusal pathologies were collected by means of structured questionnaires submitted to the students. Bivariate analysis was used to determine the existence of association between the severity of the occlusal pathologies and the other associated factors.RESULTS: The prevalence of malocclusion was 63.3% and there was no statistically significant sex differences of DAI scores (P>0.050). Twenty-four percent had a handicapping malocclusion that needed mandatory treatment. A severe malocclusion for which treatment was highly desirable was recorded in 18% of the adolescents and 21.3% had a definite malocclusion for which treatment was elective. The bivariate analysis revealed a positive association between the variable "dissatisfaction on smiling related to occlusal problems" and the DAI scores (P<0.050).CONCLUSIONS: These findings demonstrate the need of implementation of immediate preventive-interceptive programs by the local government health authorities.