Comparison of Beta and ANB Angles for Evaluation of Sagittal Skeletal Discrepancy: A Cephalometric Study.

Aim: Diagnosis in orthodontic cases and treatment planning is a precise assessment of sagittal jaw relationship. A number of angular and linear measurements have been used to attain correct diagnosis. The present study is done to compare beta angle and A point-nasion-B point (ANB) angle for sagittal skeletal discrepancies.
Materials and Methods: A total of 105 subjects were included in between the age group of 18 and 24 years and were categorized based on the skeletal patterns as class I, class II, and class III having a sample of 35 in each group. Based on the ANB angle and patients' profile, the sample was divided into different skeletal groups. Beta angle is the angle amid the perpendicular from C to B line through point A and the A-B line. Analysis of variance (ANOVA) and post hoc Scheffe's test were applied to analyze dependent variables. The level of significance was set at p-value 0.05.
Results: The mean scores of ANB for class I skeletal pattern were 2.46 ± 0.460, for class II, 5.64 ± 1.258, and for class III, -1.03 ± 1.618. Similarly, significant differences were observed in beta angle for class I skeletal pattern as 31.71 ± 3.885, for class II, 24.97 ± 2.162, and for class III, 39.26 ± 3.649.
Conclusion: Both ANB and beta angle showed significant differences with different skeletal patterns.
Clinical Significance: Both ANB and beta angle are awfully supportive diagnostic measurements to scrutinize sagittal jaw relationship.