evaluation of orthodontic treatment need by patient-based methods compared with normative method

background: a comprehensive system of assessing orthodontic need requires the integration of normative clinical measures with patient-based indicators. this study sought to discover weather an oral health-related quality of life measure or aesthetic component of index of orthodontic treatment need (ac-iotn) could be used as a predictor of orthodontic treatment need. factors affecting the judgment of patient and dentist about this need are discussed. materials and methods: oral examination on 597 iranian students between 13 years and 18 years was done to reach the grade of dental health component (dhc). the child oral health impact profile (cohip) and ac-iotn were recorded. the diagnostic values of subjective tests were assessed. multiple logistic regressions were applied to investigate the role of variables in the persons’ perceptions. results: half of the 570 eligible students did not need orthodontic treatment either on professional or self-assessment; 60% of patients with definite need had a distinct impact on their quality of life. the specificity of ac to detect the healthy persons was excellent (0.99) but its sensitivity was low (0.08). cohip score gave a better sensitivity but its specificity was 50%. caries experience, quality of life, father’s education, and brushing habits were the factors relating to the same judgment of persons and dentists ( p < 0.02). conclusion: regarding the discrepancies between two assessment methods, present instruments did not meet the predictor’s competencies. the patient-based methods could not substitute the professional assessment, but by identification, the persons with higher impacts would benefit the prioritization process. key words: adolescents, oral health-related quality of life, orthodontic treatment need