RESUMEN
The planning of orthodontic treatment within a public health system requires information on the orthodontic treatment needs of the population. The aims of this study were to assess the student, parent and clinician normative need and demand for orthodontic treatment in a sample of Iranian students using the IOTN and to compare the treatment need levels according to sex and socio-economic status of the students and parents in urban and rural areas. A sample of 427, 17-year-old students was selected randomly from schools in Abade. A questionnaire of family socioeconomic status was proposed to the parents. All the students were examined according to the Aesthetic and Dental Health components [AC and DHC] of Index of Orthodontic Treatment Need. Students' and parents' perceived need was also assessed using AC. According to DHC classification, 18.7% of the students were in the "no need"; 35.6% in the "border line" and 45.7% in the "definite need" groups. The same categories for students assessed by the dentist were 66%, 30.2% and 3.7% respectively. AC assessment by students and parents entitled even more students in "no need" category. Sex and family income were the major factors in predicting orthodontic treatment demand [P<0.05]. Orthodontic demand was highly related to the AC score and this component is of more value in predicting students demand instead of DHC