Background: This study aimed to compare the quantitative and qualitative components of IOTN index in determining the orthodontic treatment needed in High school students in Ahvaz, Iran.
Methods: This cross-sectional study was performed on 356 students aged 15-18 years. The samples were selected by cluster stratified method and the information was collected using IOTN index and clinical examinations. Statistical data were obtained using the descriptive analysis and chi-square test (P <0.05).
Results: The findings showed that 51.94% of males and 80.5% of females had no or little treatment need, 17.94% of males and 3% of females had moderate and 30.12% of males and 16.5% of females had severe or extreme treatment needs. Regarding the aesthetic component of (AC), based on the student’s point of view, 76.5% of males and 98.8% of females had no or little need, 15.2% of males and 1.3% of females had moderate need and 8.3% of males and 0% of females had severe or extreme treatment need. According to the dentist's opinion, 93.6% of males and 90% of females had no or little need, 5.1% of males and 4.5% of females had moderate needs, 1.3% of males and 5.5% of females had definite needs for treatment. Comparing the DHC and the AC showed that the DHC-based orthodontic treatment need is higher.
Conclusion: Occlusion-based judgment is more accurate and less complex. Aesthetic-based judgment is descriptive, indefinite, and individualized, and depends on a variety of social, psychological, cultural, and ethnic factors, and is more complex. Therefore, in order to achieve a better quality of life, it is recommended to consider the aesthetic and appearance-related factors based on the patient's opinion.