The relation between W angle and other methods used to assess the sagittal jaw relationship


Background: This study aimed to evaluate the mean value for the W angle in Iraqi adults with a Class I, II, and IIIskeletal relations and to verify the existence of sexual dimorphism, also to study the correlation between this anglewith the other methods (ANB, Wits appraisal, BETA angle, YEN angle) used for evaluation of the antero-posterior (AP)jaw relationship.Materials and methods: One hundred and fifty-two cephalometric radiographs of patients between the age of 18and 25 years were selected. They were again subdivided into Classes I, II, and III groups on the basis of Beta angle,Wits appraisal, and ANB angle, traced using AUTO CAD 2007. The W angle was measured between theperpendicular from point M on S–G line and the M–G line. The mean and the standard deviation for the W anglewere calculated. Independent sample t- test, the one-way analysis of variance, LSD and Pearson correlation wereobtained.Results: The results showed that a patient with a W angle between 51 and 56 degrees can be considered to have aClass I skeletal pattern. With an angle less than 51 degrees, patients are considered to have a skeletal Class IIrelationship and with an angle greater than 56 degrees, patients have a skeletal Class III and there is significantdifference in the mean value of W angle among the three skeletal patterns with a no gender difference. The Wangle had a negative significant relation with ANB in all three classes and with WITS appraisal in class III group, while ithad a positive significant relation with BETA and YEN angles in all the three skeletal relations