A BSTRACT Background: Evaluating sagittal skeletal relationships is essential in orthodontic diagnosis and treatment planning. The newer cephalometric measures, Yen angle and W angle, depend on stable skeletal landmarks and are less influenced by jaw rotation or cranial base variations. Aim: This study aimed to compare the values of the Yen and W angles in the Bodo tribal population of Assam (North Eastern State of India) with the established norms proposed by Neela et al . and Bhad et al . across skeletal Class I, II, and III patterns. Materials and Methods: Pretreatment lateral cephalograms of Bodo individuals were analyzed to measure the Yen and W angles in Class I, II, and III skeletal relationships. The results were statistically compared with the original normative data using independent t-tests. Results: The mean Yen angle values for the Bodo population were 123.5° for Class I, 114.7° for Class II, and 132.65° for Class III. Compared to a study by Neela et al. , significant differences were found in Class I ( P = 0.007) and Class III ( P = 0.018), but there was no significant variation in Class II ( P = 0.941). The W angle values for the Bodo group were 55.1° for Class I, 50.1° for Class II, and 62.3° for Class III, with Class III showing a statistically significant increase compared to Bhad et al . ( P < 0.001). The differences in Class I and II were not statistically significant. Conclusion: The Bodo tribe exhibits distinct sagittal profiles particularly in Class I and III, underscoring the inadequacy of generalized cephalometric norms and the need for ethnic-specific reference values.
Khushal et al. (Mon,) studied this question.