The relationship between normative orthodontic treatment need and oral health-related quality of life

Objectives: The first objective was to assess whether having had orthodontic treatment affected the levels of oral health-related quality of life impacts in Brazilian adolescents. A second objective was to assess the relationship between a normative clinical measure of orthodontic treatment need and two measures of oral health-related quality of life. Methods: A cross-sectional study was conducted in Bauru, SP, Brazil, on 1675 randomly selected adolescents aged between 15 and 16 years. Adolescents were clinically examined using the Index of Orthodontic Treatment Need (IOTN). Two oral health-related quality of life measures, namely the Oral Impacts on Daily Performance (OIDP) and the shortened version of the Oral Health Impacts Profile (OHIP-14) were used to assess the adolescents' oral health-related impacts. Multiple logistic regression was used in the data analysis. Results: Adolescents who had completed orthodontic treatment reported less oral health impacts on their daily life activities than those currently under treatment or those who never had any treatment. Combining the IOTN index with either of the two oral health-related quality of life measures used in this study provided more information about the adolescents' perceived satisfaction with their appearance than the IOTN on its own. Conclusion: Current methods of assessing orthodontic need should be complemented by oral health-related quality of life measures with valid psychometric properties, and measures of perceived need.