Wits appraisal and Tweed triangle for a sample of Iraqi adults

Abstract

ABSTRACT
Background: This study aimed to establish the normal value of Wits appraisal and Tweed triangle for a sample of Iraqi
adults and to verify the existence of sexual dimorphism.
Materials and Methods: 95 dental students (41 males and 54 females) having normal occlusion and acceptable
facial profile were chosen for this study. Each student was subjected to clinical examination and digital true lateral
cephalometric radiograph. The radiographs were analyzed using AutoCAD 2007 to measure the distance
representing the Wits appraisal and the angles representing Tweed triangle. Descriptive statistics were obtained for
the measurements for both genders separately and for total sample; independent samples t-test was performed to
evaluate the gender difference.
Results: The results indicated that the mean value of Wits appraisal was higher in males than females with a nonsignificant
difference between both genders, on the other hand, the Frankfort- mandibular plane angle was higher in
males than females while the Frankfort- mandibular incisor angle was higher in females than males and mandibular
incisor- mandibular plane angle was nearly similar in both genders with a non-significant difference.
Conclusions: The normal values of Wits appraisal and Tweed Triangle were established. The Iraqi sample showed Wits
appraisal of females near to that of Jacobson while of males was higher. Regarding Tweed triangle, both genders
showed more proclination of lower incisors than of Tweed with a Frankfort- mandibular plane angle near to that of
Tweed.
Key words: Tweed triangle, Wits appraisal. (J Bagh Coll Dentistry 2011;23(4):134-140).