Oral health-related quality of life (OHRQoL) is an important aspect of health 
outcomes and its assessment should be made using validated instruments. The 
psychosocial impact of dental aesthetics questionnaire (PIDAQ) is an OHRQoL 
instrument that assesses the psychosocial impact of dental aesthetics was 
developed and validated for use on young adults. The aim of the present study 
was to assess the reliability, validity, and applicability of the PIDAQ for 
young adults in Brazil. After translation and cross-cultural adaptation, the 
questionnaire was completed by 245 individuals (124 males and 121 females) aged 
18-30 years from the city of Belo Horizonte, Brazil. In order to test 
discriminant validity, the subjects were examined for the presence or absence of 
malocclusion based on the dental aesthetic index criteria. Dental examinations 
were carried out by a previously calibrated examiner [weighted kappa = 
0.64-1.00, intraclass correlation coefficient (ICC) = 0.78-1.00]. Internal 
consistency measured by Cronbach's alpha of the subscales was between 0.75 and 
0.91 and test-retest reliability was assessed using the ICC, which ranged from 
0.89 to 0.99 for dental self-confidence and social impact, thereby revealing 
satisfactory reliability. Discriminant validity revealed that subjects without 
malocclusion had different PIDAQ scores when compared with those with 
malocclusion. The results suggest that the Brazilian version of the PIDAQ has 
satisfactory psychometric properties and is thus applicable to young adults in 
Brazil. Further research is needed to assess these properties in population 
studies.