1 Dental Research Center, Tehran University of Medical Sciences; Professor, Orthodontics department, Tehran University of Medical Sciences
2 Teaching assistant, Orthodontics Department, Tehran University of Medical Sciences
3 Research advisor, dental research center, Tehran University of Medical Sciences
Aim: anterio-posterior discrepancies and differentiating the involved problems make a major part of our diagnosis and treatment. The main goal of this study was to compare the
Materials and methods: In this cross sectional study, 105 pre-treatment lateral cephalograms (42 males and 63 females; 12±3 years old) The cephalograms were classified according to Angle classification. In all cephalograms, the ANB angel, Wits analysis, β angel, µ angel, Jaraback index and Bjork angels were measured.
Results: The highest accordance between clinical observation and Wits appraisal was seen in class III group. The most accordance of the ANB angel was in the class II group.The best correlation was found between µ angel and β angel (r=0.912). The correlation of ANB angel with µ angel was the weakest (r=0.769).The results showed that when angle is smaller than 12.7 degrees, the patient is skeletal class II and the patients whose angle is larger than 19.1 degrees are classified in class III group.
Conclusion: All of four sagittal parameters (ANB angle, Wits, β angle and µ angle) were well-correlated. The best correlation was found between µ angel and β angel. The correlation of ANB angel with µ angel was the weakest. angle and angle are proper tools to show skeletal class II and class III, but these angles cannot differentiate prognatic or retrognatic jaw.